https://github.com/uBlockOrigin/uBOL-home/wiki/Frequently-as... has a few of the more practical concrete examples. Namely content can load without the blocker being ready to filter, CNAME cloaking can't be handled properly (in Chrom* at least), and the filter rules aren't as flexible.
Interestingly, the rule count limits themselves do not (currently) seem to be much an issue despite it being one of the more common concerns on the original MV3 announcement.
Interestingly, the rule count limits themselves do not (currently) seem to be much an issue despite it being one of the more common concerns on the original MV3 announcement.