What I find interesting about projects like this is how much of the OS "feel" doesn't survive emulation. The visual layer comes through fine, but the things that actually defined the experience — keyboard click latency, the specific mouse acceleration curves of period hardware, the way a CRT scanline gave System 7 fonts a totally different texture than a sharp LCD does, the audible click-thunk of Atari ST or early Mac dialogs — none of that gets preserved.
Run System 7 in an emulator and the menus look right, but the input feels wrong. What we're really preserving in these collections is the screen output, not the interaction. Which is fine for an archive — just worth being honest it's a museum of appearances, not of use.
I tend to associate the Amiga with razor-sharp interlaced displays, so seeing 640x400 noninterlaced in an emulator leaves something missing. The Amiga also had an unusually smooth mouse response due to its interrupt prioritization and use of hardware sprites for the mouse cursor. I had never seen a mouse move as buttery-smooth as it did on the Amiga. Again, this is not captured via emulation; not even my MiSTer seems to get it right.