Thing is though, most consumer networking gear is capable of a maximum of 1gbit, so to even take advantage of 2gig or 2.5gig you at least need a router with a 2.5gig uplink. If you have this you can have a couple of people on the network using a gig each.
My setup is a 1.2g cable connection going into a 2.5g port on my router, with a couple of servers connected to the router over 10g. This basically lets me download off of my servers at the full speed of the network but the rest of my devices are limited to 1gig.
Going up to 20gig would require a large investment to see the benefits. First you would need a router with a 25g uplink port, which is really only going to be found on a specific tier of “enterprise” gear. These routers aren’t going to have a bunch of ports so you are going to need to dump the output either to a 25g switch or a couple of 10g switches (probably the most cost-effective option). From there you can distribute out to 20 machines at 1g.
Anyway, you are definitely right about the aim of a service like this but to see the benefits of a 20g connection would require some very expensive and specialized equipment.
Just casual racism is all.