The number I was referring to was the new 5, 6 etc., not the year when all the updates to 802.11 are rolled up into a new package. Regardless, the technology is advancing and while 802.11ac is the latest we can currently get, ax will be along sooner or later. Don't forget, this sort of thing has happened with every change, such as from b to g to n etc.. The spec is proposed, manufacturers roll out pre spec hardware to test and then the final version. Incidentally, at one time 802.11n was as far as 2.4 GHz was supposed to go. Then ax arrived, which provides improved performance on 2.4 GHz, as well as 5. Back when WiFi first started becoming popular, with 802.11b, we were typically running 10 Mb half duplex Ethernet. Since then we've moved to full duplex 100 Mb, Gb and even 10 Gb and WiFi more or less keeps up. I was on one job last week, where CAT6a cable was specified to the access points, because they had 10 Gb Ethernet ports. Everything else was just plain CAT6.
BTW, even stuff like IP changes with time. Take a look at the RFCs and you'll see plenty that are superseded by newer versions.
I haven't lost my mind. It's around here...somewhere...