I think it has to do with the fact that YouTube basically never had serious competitors except in the very early days. The only semi-competition is now TikTok, which they copied with YouTube Shorts. But their regular video business has been completely unchallenged for 15 years. In an environment without competition, efficiency and effectiveness of internal decision making can easily degrade over time.

Yep and that also explains why YouTube's comments section is the biggest dumpster fire of outright scams I've ever seen: why would they care?