It's clear that YouTube doesn't want you to have much influence over your feed. You can't even ban specific channels from being shown to you, which would be the simplest thing to implement, and other knobs that previously existed were silently removed.

Since Google does nothing that isn't based on metrics, we can deduce that they have data to show that giving people settings to focus the recommendations on what they want reduces total watch time. We'll only get an AI filter if it turns out that AI slop offends people so much that they disengage with YouTube altogether, which outside of HN and similar bubbles, I don't yet see happening.