I think that even if you stripped out non-professional vibe coders from the equation - the problem is still there, and will keep compounding.
For one of my green-field projects that I just vibe-coded with AI's (where Claude, Codex and Gemini critique each other's design and code), a PR could go through many iterations (commits) until every AI approves, and if every commit runs the CI, it'd be very slow. So I eventually come up with a mechanism to only run CI when all reviewers approve. That improves things a lot.
Those limitations were put in place for a reason, and using the work-around feels dirty. I recognize that all platforms are flawed once you start to do more than they offer, but I feel that with AI its easier to build the plumbing around it.
The question shouldn't be: can you do this, but 'is this the right thing to do'?
So you can reduce the free resources they consume with the slop.
Nothing about complexity, simply github setup such an easy automated system but AI cares not about whether their commit+push is going to kcik off a whole rebuild.
Same thing happens when I run docker build loops. The AI gives very little shit, unless I tell it, about not busting cache; so it'll sit there for hours making minor changes just to make a 30 minute build.
AI has not concern about how long anything takes, in general, but it if it's just waiting for it to return, it won't get impatient.