That's not really how curation works, you post something once and that post 2 years ago may have gotten you more than just the rewards, not counting what they'd be now having remained staked, etc. You get the chance to followers, interactions, possible autovotes, tips, etc from posts, reposting not only has the chance to get the same voters to vote on duplicate content but also opens up a gray area to what people think they can get away with if we only removed x $ of rewards compared to the last one, etc. It's best to just not accept rewards if you want to cross-post things for the visibility/attention/etc so it's a universal rule rather than depending on each case.

Usually we would've warned you first but an account of your age and reputation should be aware by now.