Going forward, both AMD and Intel have built 2.5 gbe controllers into their cpus and chipsets, so if partners want to use it, it's there. As such you will see it start to be rolled out even in consumer products over the next couple years. The initial rollout was hampered by a few "light errata" with intel's controller implementation (basically it didn't work at 2.5 gbit speeds at all, oops) but we're a couple gens into it now and it's going forward. AMD has one on their chips as well (if not faster, I want to say AMD has 10gbe in their dies for Ryzen Embedded usage).
(expecting it in a 2020-era product, however, is perhaps not reasonable, like I said this is something that has changed mostly in the last year or so. Although granted a Thinkpad is not a consumer product so maybe it should have been ahead of the curve. But I don't think multigig had penetrated even professional spaces that well in 2020, except perhaps 10gbe in certain high-end segments.)
The gotcha with multi-gig has always been switches, very few cheap switches existed and the ones that did were mostly SFP+ and not 10GBase-T (i.e. you either need new wiring anyway, or you pay $50 a set for SFP+ adapters). This is somewhat better with 2.5gbe, there are now some 8-port switches under $200, but it's still a long way from 1gbe where you can get a nice 8-port for like $25. Hopefully it is a matter of volume and prices come down over time.
I'm a little miffed that 10gbe got passed over - 2.5gbe seems like a half-measure, and the wiring argument isn't very compelling to me. If they implemented 10gbe you could always allow fallback to 2.5gbe if that's what the signal quality can support (many <10 meter Cat5e runs are good enough for full 10gbe anyway) and it's a much more significant step than 1->2.5gbit. And the economy of scale here is significant, if consumer stuff goes 2.5 then that's what gets made and 10gbit remains expensive.
Anyway currently I am eyeballing the Netgear MS510TXM - this does pretty much what I want in terms of giving me a few SFP ports for fiber links (or server usage - SFP does have lower latency), a few 10gbase-T links for consumer PCs with Aquantia 10gbit nics, and a few 2.5 gbit ports for consumer junk. At $500 it would be nice if it was a 12-port, but it checks most of the boxes at least.