This is because they're not trying to give you stuff you'd generally like given your entire history. The recommendation feature powers the part of YouTube that auto-plays the upcoming video.

So e.g. if I go and view Russian dashcam videos they're going to automatically play more of them, even though I've shown no prior interest in that topic.

Having two systems for recommendations would introduce a lot of UI complexity, so I can see why they didn't go for that, and why the recommendations are consequently tuned for people who are actively watching videos on some topic right now.