You could of course use some kind of socket or connetor for supercap, but as they last far less than I thought then I get why it doesn’t make sense. This thinkstation I’m writing with in my garage I got for free at old office is from 2011 and it’s still running original cmos battery. No idea if there’s any juice left on it, but at least it doesn’t complain anything at boot and once it refuses to boot it’ll become e-waste immediately (I do metal working, fix cars etc at the garage, so internals of this thing are far from clean, I think this is 3rd or 4th hardware for 10 years in here with only the SSD moved from setup to another).