I have installed ExFat on RL8.6 and now notice, that I can’t write to an 512 GB Sandisk USB.
However, writing the same data to an 256 GB Sandisk runs without any problem
Well no, but in fact, as I check it now, I only see it in Rocky because of epel but for Rocky 9 it does exist as a package in baseos. In which case, for Rocky 9, no need to install epel-release.
Amended my reply above, to reflect that epel-release needs to be installed to get that particular package for Rocky 8.