I don't think this is correct. I distinctly remember some scroll-enabled UI elements on Windows displaying a completely greyed out scrollbar when the content

I don't think this is correct. I distinctly remember some scroll-enabled UI elements on Windows displaying a completely greyed out scrollbar when the content wasn't actually scrollable. Indeed, I can verify this today with PUTTYGEN.EXE even on Windows 11, where if I generate an RSA-2048 key there is an active scrollbar, while if I generate an Ed25519 key which is 1/8 the size, there is a greyed out scrollbar. That having been said, I think this is the right way to do things. The greyed out scrollbar tells me that control is meant to be scrollable. So if I do something that changes the content, I can expect to be able to scroll it.