Yeah, it's... an option, I guess, if you've got the dough. Many of us don't have that kind of budget so we look for some of those experts who have blogs and youtube channels.
In centuries past, if there were a mathematician who wanted to know more about botany, it was the most normal thing in the world for him to contact a botanist interested in math and trade the knowledge. This usually involved one going to stay at the home/studio/estate/whatever of the other for what today would be considered a long period of time. The upside was that you could learn all you needed to know from what was as good a source as you were likely to ever find.
If you think about a modern version of this model, you could get all the information you need on the subject you're interested in and it wouldn't cost you a nickel. We have the internet, they didn't. Might even get a pretty good friend out of the deal.
Of course you need knowledge to trade, and pretty deep knowledge at that. At the same time, if there is an arborist out there looking to learn programming, and you have heaven only knows how many fruit trees on your property, what do you have to lose by checking his/her clients for references? You can teach him/her programming. They can teach you what you need to know to care for your property. You guys can each contact each other's references to make sure you're actually experts in your respective fields. There doesn't seem to be any risk in trying? (Unless I'm missing it?)
It just seems a really easy fix to the money problem. And you can access knowledge from everyone from arborists and physicists to dance teachers and electric motorcycle engineers to international development experts and nanotech engineers. The sky would be the limit.
On the other hand, I can basically guarantee you that someone somewhere is willing to pay money for an arterial stent, and somewhere else there is a world-class expert mathematician who will accept money in exchange for tutoring.
I'm usually contacted by engineers or companies that do market surveys and have the detailed knowledge of my background, so doing a lot of those (which are usually also compensated at like 40 to 60 per hour) pays off.
I haven't been able to engage in any of these for two years now because I moved to the US on an H1B visa, but the offers still keep on coming. I got like five in 2019 and two in 2020 and I had to say no.
You can find one for less, though, if you ever find yourself wanting one. Mentor.io is a good place for it.