Hi, thanks for your reply.
About the Windows situation: I asked because the non app version V1 worked exactly like I mentioned: Install it using one user, and it works for every other user of that machine. I know that the new app installer seems to work differently, but still, it is a bit inconvenient to do the activation all over again for each user of the PC and I was a bit worried it might trigger an activation lock. Possibly, you could have differentiated here between private licenses and school/commercial licenses.
On an iPad, sadly, there is no multi-user mode, no. It is a managed device via Screen Time (so I can control what my son can do on it etc. via my own iPad) but it is using his AppleID and I can't simply swap that out and change back (well you can change it, but your software activation won't stick, because it is linked to your AppleID).