In the past, as long as it's only 1 or 2 years, there weren't really any readmission issues as long as your previous grades weren't terrible. I've been readmitted, and had a few friends readmitted. There are lots of reasons that students take a gap year, some of which are well outside the students' control, so it's a fairly common occurrence that colleges have provisions for.

However, if you go too long, prerequisites start to change, credits start to expire, etc., so even if you're readmitted that can be problematic.

And there's the caveat that Covid may have all sorts of effects in the coming years.