There's a lot of good arguments in this thread about incentives: extremely convincing about why current incentives lead to exactly this behaviour, and also why creating better incentives is a very hard problem.

If we grant that good carrots are hard to grow, what's the argument against leaning into the stick? Change university policies and processes so that getting caught fabricating data or submitting a paper with LLM hallucinations is a career ending event. Tip the expected value of unethical behaviours in favour of avoiding them. Maybe we can't change the odds of getting caught but we certainly can change the impact.

This would not be easy, but maybe it's more tractable than changing positive incentives.