sloppers can just keep burning new accounts (as long as they have access to new IP addresses) while real developers deserving of praise and reputation thrive.

Becoming a Debian developer requires you to meet an existing Debian developer in person and have your public key signed by them. It's not possible to keep burning new accounts unless you go and meet a different Debian developer each time and there's a limited number of them in each region and they usually meet together, so more than one person will see your face.

Yep. I'm not familiar with Debian's strategy specifically, but generally, I think any new contributor to a project should be subject to heightened scrutiny. My policy is that new contributors should start small and develop a rapport with the maintainers before submitting more ambitious (and for the maintainers, more costly to review) large and/or critical path PRs. It was a good policy before LLMs and I think it remains a pretty robust method of weeding out irresponsible devs without wasting a ton of maintainer time. There are simply more slop PRs to reject sight unseen these days, which is admittedly very annoying, but the process is much the same as it's always been.

I'll admit I don't maintain any projects anywhere near the popularity or volume of the Debian project, so I'm not really sure what the view is from their vantage point.