Probably the algorithm got trained by 3 year olds, who keep on watching the same videos over and over again.
I completely skip the home page, I go for subscriptions directly.
I dont know why you are suprised that google knows things. You order stuff online, you get a mail about it.
You go somewhere, your phone tacks you. It will even ask if you enjoyed your stay at a certain restaurant. The one you looked up the address on google and used maps to go there. At the end of the month, I get an email telling em that I was in 4 countries last month and spent 30 hours in a car and walked so many km.
You dont even have to be a conspirator theorist to see the pattern here, it happens in front of your own eyes, and it is written in the terms of service. All you can turn off, if you want to get a mail about it.