Don't want to burst this bubble either, but I have yet to have one of their batteries last nearly that long--some as short as six months. (I haven't even had most of mine for two years yet but have probably replaced nearly every single battery, some multiple times.)
Not Mike, but...Xiaomi devices are not standard ZHA 1.2 devices. Hubitat is (among other things) a ZHA 1.2 hub. Xiaomi devices just happen to be close enough to ZHA that the community has discovered ways to "trick" them into working, and they do for many people. But you have to be careful with how you build your ZigBee mesh, otherwise you will likely have problems. While standard ZHA 1.2 devices, like Iris v2 and later devices, vary in quality, all should theoretically work on a standard ZHA 1.2 network without problems--or at least not any more problems than mesh networks otherwise cause some people.
I completely agree with the decision to not officially support these and even more with not recommending them to new users. Standard ZHA 1.2 (or ZigBee 3.0) devices require no additional special consideration and are certainly easier for any user, old or new. If you know what you're doing (and understand the technical issues), Xiaomi devices are certainly an option you can turn to, as many have.
Do you mean "Iris"? Those are standard ZHA 1.2 devices, as I stated above, and in no way suffer from problems on standard ZHA 1.2 networks like the Xiaomi devices do. (Again, it is possible to build a bad mesh--or none--that will have problems with any ZigBee device, but that is a different issue. Iris plugs in particular also seem to have a problem on the Z-Wave side for some people [it's a ZigBee plug with a built-in Z-Wave repeater], but that is a different issue.) Hubitat does not manufacture or brand their own sensors, and their approach seems to be to add as much official support for standard ZigBee and Z-Wave devices as possible.