It feels like the Windows Registry is one of those well-intentioned ideas that ended up being a tremendous mess in actual implementation. "Let's use a central database to store things that the OS, drivers, and UI need to access" somehow became "half assed KV dumping ground for every process and their dog to litter with whatever while acting as a singular bottleneck". See also: https://news.ycombinator.com/item?id=322…
It's developer error. It'd be the same as a game on Linux filling up a conf file or a database with duplicates. Does Linux have mechanisms to guard against that? Didn't think so.
Sure. ulimit or cgroups can.