Making bad code run faster is overstepping the boundaries.
We don't prioritize bad code for optimization. See usage of 'with' in Javascript. We don't actively try to make it worse, but whenever a decision is presented which regresses 'with' performance for gains somewhere else, it'll probably be taken because we don't care about 'with' running fast.
But the example I mentioned: histograms of max GC pause times on a particular website. Or particularly bad janks, or long amounts of time spent in JS which might be the result of poor JS execution..
None of these optimize "bad code". They're just standard platform performance optimizations that help all programs. That will include "bad" programs as well.
If mozilla can't see how utterly insane this is then there is no hope left.
What about the relationship between you/Mozilla and the firefox users? This thread is evidence that at least some of the users are not happy that you are (in their eyes) sacrificing their privacy for future performance gains.
A program written by a developer and used by a user is a relationship between that developer and the user. I just work on the platform that allows that relationship to exist. I feel it's overstepping our boundaries as platform providers to say "we're not going to make this platform faster for you because we think developers are writing bad code using that performance as a crutch".
It feels like I'd be setting myself up as a self-appointed clergy over moral matters in software development. It's not a hat I'm comfortable with.