not just since 1998
Loads of stuff made in the 80s is at its limit at 1080p. A lot of those films were made to look grainy by pushing the film. When you scan them at higher resolution you don't get more detail, just more grain. I think 4K is probably the limit for 1:1.85 content. You can get a bit more for 4:3 or scope.
I think people will very quickly realise that they don't care. We've been watching 2k projection at cinemas for years and nobody is complaining.