I'm #3 & #4, except:
#3 is a home-built 486/66 PC with a VGA display, 64MB of RAM and 11GB distributed over two (2) hard drives. Who knows? I may need that parallel-cable, 2-port MIDI interface again someday, not to mention the Cakewalk Pro Audio 9 (which I actually got to work on my Win10 notebook, so maybe not so much);
#4 is something that, after many upgrades over many years, I have mostly gotten over. But I definitely obsessively back up everything music-related before any upgrades (which you should do anyway, right?).