I could buy a 6E Intel wifi card for next to nothing, yet it doesn't seem to be possible to buy a consumer router with SFP+ or SFP28 fiber and 6E, so I'm stuck as to how I am supposed to use these faster WIFI endpoints?
Communicating with a NAS on your home network for large file transfers is really the only use I can see. It's not like >gigabit consumer connections exist anywhere, though there is a bit of a chicken and egg situation there of course.
Init7.ch supports up to 25 gb/s, but finding the right combination of small devices like consumer routers and notebooks to achieve much more than 1 gb/s is difficult. I.e. with a desktop it's easy enough to use a 10 gigabit card, with a notebook you are often stuck with inbuilt gb Ethernet and maximizing the wifi instead.
I can upgrade to 1.5/1 gigabit from my provider, but I'm satisfied with 1/1 right now. From what I've heard the reason the upgrade isn't symmetrical is that the ONT that they provide is the bottleneck.
I've seen posts on here by Swiss people who are able to get 10/10 as well.
