I'd expect it to just resize the image as needed....

I also thought that, but I think the current limitation (4096 x 4096) is reasonable and was introduced to avoid to scale huge things and mitigate resource exhaustion in thumb generation.

Maybe since "we live in interesting times" we can increase such limit indeed also, but that logic makes some sense (but terrible user experience, I agree lol)

Oh, I miss-understood the problem statement. The 4096 limit is on the size of the image that we can resize from...