GitLab VPE here.
Historically the dominant source of outage minutes is indeed features that didn't scale (70%).
However, We've made great strides in the past 6 months on QA and release management and it's yielded a marked improvement in availability. The last week has been an exception to that.
We're in the midst of a move from Azure to GCP, and once that is done, we're going to rebuild out system to be entirely automated which will eliminate a class of manual mistakes.
Imagine a gitlab product that goes into operation, and gets updated with a good load of features every 3 or 6 months? The ones they replace with is thoroughly tested internally?