25GBit/S on macOS and iOS

1G has wide adoption, runs on any cheap 5e cable and has low power draw. 10G may or may not run on same cables and has 4-7x the power consumption. That means more heat, more bills, stiffer cables that are harder to manage and so on. I dropped 10G/2.5G attempts at home after realizing that it will mean way to much heat in a TV cabinet somewhere.

A lot of devices don't need anything faster either. If you run, for instance, monitoring setup with POE cameras, you may even use 100Mbit as it's sufficient AND some end devices will have just that (and to my surprise there are still plenty of 100Mbit devices being sold). A lot of people don't realize how many TV's still use 100Mbit. Mine does, yet it can play any 4k video I found. And it's still way above what is actually needed. A 20GB/hour video file is way to big to be reliably played with a lot of capable but slightly older smart devices, tv boxes and so on, and that is HALF of what 100Mbit can provide.

Also - wireless. It's not exactly obvious to have decent wifi coverage at a home. Often it requires effort to be done right. So even when on 25G it won't matter that much if perceived performance suffers because of laptop <-> wireless access point setup.

Then there is storage - getting 50-100MB/s performance is achievable using one cheap 3.5" drive. But if you need some bigger storage, redundancy, or better performance, you need a fairly large investment. It's not always needed and not always justified.

2.5G is showing up more and more, it's not a huge jump, but unlike 10G, it does show up in consumer devices randomly - SFF PCs, stock ISP routers. And it seems to have much less power draw as well.

So 10G is present where it was most desired - for trunk connections to ISP/between major elements like main switch and NAS; where people work on large volumes of video and so on. And obvious in commercial/enterprise setups. But it's not worth going "let's slap 25G on all ports for this consumer device".

https://www.rfc-editor.org/rfc/rfc2549

I think a lot of it is down to the realities that most people are only really interacting with the internet at home, and for the most part, speeds over 1gb outside data centers was pretty rare. So very little need to upgrade.

No mass movement to upgrade, means fewer component sales, lower production means economies of scale don't apply. Meaning you're stuck in relatively early adopter territory for a while.

I upgraded my home lan as well last year, my main switch is now 10gb copper, my desktop and nas are the only devices with 10g nics, a few others are 2.5, and my secondary switches are all 2.5g to save money.

Standard? Definitely not. Only high end prosumer gear came with gigabit as standard in the early 00's. The vast majority of affordable consumer gear still had 10/100 Fast Ethernet well into late 00's and I even saw new laptops with it even early 2010's(!).

Asking because I'm looking for something suitable for a homelab (using Mellanox 40GbE cards) that's in the same room I tend to occupy during the day.

When I used very early Mellanox switches (years ago), they were only suitable only for datacenters. aka permanent super noisy jet engine mode

Their 1U 10Gb/s Infiniband switch is still the noisiest piece of equipment I ever made the mistake of buying! (!!!)

So, maybe Apple added those drivers for people using ConnectX adapters with Mac Pros?

Yes. Did you ever been in an actual DC and handled 10G-T cables and ports?

They are hot, even in the DC with HVAC running below 20°C.

And there is only one type of the systems which can easily accept that amount amount of heat - the desktop *ATX systems, for which you can just go and buy a 10G PCI-E card.

For everything else the amount of heat is too much.

Random example (I don't know the seller): https://www.ebay.com/itm/166609931874

That's $39.99 for a dual port 25GbE card, and that generation are still on the official supported list for lots of things.