"over time software should converge on being bug free"

Yeah, and the way that's done is by refactoring things, removing buggy/deprecated things, and not adding any more new features/requirements... So, pick your poison, I guess? I'd love to go move on to the next job as much as the next person, but somebody still has to be paid to do those things. I don't see what the significant difference is there with free-with-paid-support, if you pay for it up front you're still paying the same cost.