I rarely say "this new update is buggy I wish I could downgrade" but honestly iPadOS 15 made me use my iPad less than ever. The experience is fine overall, but not as refined as you'd expect from iOS. There are annoying bugs here and there, especially if you try to use your iPad as a laptop, i.e. in landscape mode and a magic keyboard.
I really hope iPadOS 16 will be a real improvement. Sadly no other device, given the form factor, matches the hardware quality and performance (for now?).
Just another single-user instance.