Based on how things have been described on both sides, it actually sounds like they do a pretty good job. Oversights happen -- we're all human -- and this access was already limited to a small single-digit number of people. Given the history, it's reasonable that Arko would have had this high of a level of access and the oversight was in forgetting that when removing him.

Also it's reasonable to assume that people with that access wouldn't do something criminal/malicious, and if they did, while annoying, the situation is very easily recoverable. Especially if you're using IaC tooling as you mentioned.

If you're already taking the position that Ruby Central are "the bad guys" it's easy to assume that they're doing everything wrong, but that would be a mistake.