> The earlier you can find an issue the simpler it is to fix, so waiting until the last moment (e.g. PR) means you're spending far more time fixing issues than necessary.

Wait, does that mean that E2E tests that catch bugs are a strong signal that the team isn't doing well? How about component tests that catch bugs? Wouldn't they be better caught at the unit-test level? Do you see how your argument is flawed? - nobody is "waiting until PR to catch all bugs" but that doesn't mean that PR review can't/ shouldn't catch bugs! Sometimes even significant ones, yes.

You don't eliminate E2E tests because "you have good unit tests". You shouldn't just eliminate PR reviews because "we communicate inside the team".