I've never even worked with a code review process where outright rejecting PRs is a normal part of the process for anything other than external contributions. The normal process is more of that if you think a PR is a bad idea it's up to you to persuade the author of that. You'll certainly sometimes have the author withdraw the PR without being truly convinced, but something like "I don't like this. Rejected." would just be disregarded if you can get other people to approve it.

I think the issue is not that people make drive-by issues, the problem is that people argue about things endlessly which does not bring any value neither to the customers nor the company, that is only for the vanity of the reviewer, and many reviewer get offended when someone does not take blindly their "wisdom" and for retaliation they block code commits endlessly which is enforced by automated tools like Gitlab.