If this would be the case every wedding photographer would just use an iPhone.
Yes, phone does HDR (not always perfectly) but there is so much more to photography than trying to make shadows not black and sky as blue as possible.
Sometimes people just don't have "a feeling" on why professional photos look like professional photos. It is all about composition, angles and stuff. Sensor size is not so important if you are taking a photo of landscape and showing it on instagram.
I wouldn't be surprised to find that some measurable percentage of "official person tasked with photographing a wedding" are just using phones. These are not professional wedding photographers, but they are acting as a wedding photographer while using a phone camera. (And they are friends or family doing the task for free.)
Surely many weddings are not high expenditure events. An average person with a modern phone who takes a LOT of photos at each moment or scene will produce some good images. They may not be of the quality where you could print large poster size, but most people probably don't print larger than 11x14.
There's no doubt that a skilled photographer with good gear that is suited for the environment can do better. Phones are not a replacement for this if final result is the only criteria. But not only are not all "professional" photographers great, but a lucky amateur with a good phone cam and lots of snaps may end up with output that a layperson, including the subjects of the wedding, might not be able to see the difference of.
So your point really stands here.
However for anybody just a little bit involved the difference is huge. Simple things like depth of field can only be faked on small sensor because if physics.
HDR on phones also often look fake, imperfect and artificial. To the point that I think in 50 years people will try to fake it to get that "2020 look" as nowadays we try to get "film look of 60s".
I know I'm a weird person, but I never got the whole depth-of-field/bokeh thing. While I understand that some people want the "focus" to be the sharp center of attention, and perhaps other things to be less sharp, I never liked the "everything except the main object is super blurry" effect. In many cases, I want everything to be in focus so I can choose what to look at and enjoy.
As for HDR look, it's a bit difficult to say what neutral/normal is since it depends on SO many variables (including the brain of the viewer). So I would argue that your perception of the "fakeness" of phone HDR is because your mind is trained on images which look different. Even if there is a formal correct definition of ideal, in cases of relatively small differences it's kind of moot.
Plus, at my basic understanding I believe photogs shooting in raw are choosing to some degree how to interpret the data when they convert from RAW. Maybe they let the default converter choose, and maybe (probably) they make some choices of their own. So at this point there is no truth. There is just the subjective choices of the operator.
Even between camera/lens/software choices the results can be quite varied from what I've seen reading many camera tests, reviews, and comparisons.
Ultimately a human with a little training or some intuition/luck can make choices of how and where to shoot which probably have the greatest overall impact on the likeability of the image.
At the end of the day all these choices boils down the argument of photographer as artist vs photographer as documenter. The artists goal is to essentially decide what part they want you to focus on and how you should experince the scene so that they can elicit the emotional response they want. The documenter wants to show you as accurately and neutrally as possible what the actual scene looked like when the picture was taken. Which one you prefer is entirely dependant on what you think the purpose of a photograph should be.
The main reason is to draw your eye to the subject instead of the background. It’s also how our eyes work.
The third (related) reason is that the background often isn’t super controllable. If I’m taking portraits of someone in the woods I don’t want branches “coming out” of their heads, and those branches being blurry helps with that. At weddings if I’m photographing candids of a group of people blurring out everyone but the subject(s) is handy because people often make stupid faces. And don’t get me started on how messy bridal suites are where the girls are getting ready…
As a POC, some have. Here's Peter McKinnon [1], and Tomorrow's filmmakers [2]. The wedding is also a very controlled lighting scenario, allowing the dedicated camera to maximize its advantage. Shutter-speed matters too, which Phones have closed in on but not yet eliminated. (In my post, I called out brightly lit conditions.)
Large camera bodies are also about looking "professional". Like most people don't wanna go to banks where staff is dressed in t-shirts and shorts.
[1]: https://youtu.be/yLZJS2k2V4k [2]: https://youtu.be/6RAVCzd0MZw
To take candid photos in a dimly lit environment (evening, church, outdoors at night etc) you need a big honking flash or a lens that captures more light than the Hubble.
Every good photographer (almost) always bounces their speed light off the wall/ceiling or uses an off camera flash. I’ve taken hundreds of thousands of wedding images and never once had red eye to remove. People also don’t “startle” faster than the speed of light.
Speedlights aren’t “big honking flashes” and as long as you know what you’re doing you’re still usually at a high ISO as you don’t want the background to be super dim compared to the foreground.
Anyways, phones are especially ill suited for that environment compared to modern cameras. At f/1.4, 1/200th of a second shutter at ISO 6400 you can freeze everything but super fast motion with pretty good image quality in very dim environments. Phones absolutely cannot do that. Even pictures taken outside just after the sun sets are a smeary mess after the built in noise reduction.
Stills, IMO, would be even more of a disaster.
I don’t like carrying god knows how many pounds of weight on my shoulders with two cameras, 3 lenses, and often two speedlights on me all day. I also bring two Pelican cases of lighting equipment, a camera bag full of batteries and lenses, and an “oh shit” bad with backup cameras and lenses. That’s what I need to do a good job in any condition.
Phone camera photos look good on your phone. If you have absolutely perfect lighting they may even look good blown up to a somewhat reasonable size. Good luck getting anything useful in a dim church, on the dance floor, etc.
It’s pretty often that a mom comes along to a senior photography shoot and takes photos with their phone of me at work and then sends them to me. The quality is utterly laughable compared to what I’m capturing at the time when actually viewed on something that’s more than 6 inches diagonal.
Photographers might make silly YouTube videos trying to get clicks where they use phones on a pro shoot but that’s where it ends.
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