I've found YouTube's defaults for a lightly-used profile (my work Google account) tend to be like Charlie Kirk/Ben Shapiro owning the libs type garbage.
Comes, because statistically those youtubers are able to latch on to some viewers and this drives engagement. I believe some of that has been pay-to-win stuff, where the youtubers actively advertised and paid directly for engagement. Some of those folks are subsidized by outsiders.
Goes, because YouTube knows from studying its own business that they're capable of driving more engagement by turning people into video-obsessed alt-right Nazis. And if it's too obvious, they'll be called on it, or actively punished as a platform over essentially selling themselves out as a propaganda bullhorn to whoever's able to pay.
That being the alt-right Nazis, and those who fund them.
So it goes back and forth. YouTube doesn't always do this. It does as much of this as it possibly can, but is systemically aware that running with it causes other problems, and dials it back to stay out of trouble (and because some of the people minding the algorithms are not, themselves, alt-right Nazis).
YouTube always wants to find an algorithmic answer for everything, and is not afraid to go meta and look at larger contexts for what they do. It's a google thing. So they want, and don't want, the 'own the libs' paid-for content. It's both simple capitalism, and looking at it on a larger systemic level where there are risks to allowing their ad buys to stoke outright revolution of the country YouTube is based in.
Incognito mode doesn't make their recommendation system any better, but at least it doesn't get stuck on some stupid subject because their bs algorithm deemed it important to show the same stuff several days in a row.
What this does is to tune the recommendations for that session to what you view for that session.
If you blindly follow some pratfalls or kittens video, you'll get served up junk. If you happen to be researching some specific topic (how-tos, explainers, academics, technical topics being among my favourites), you'll tend to find you're getting recommendations that follow from that initial topic.
I still treat recommendations quite warily, but at least the ones that come up in such sessions are somewhat better than standard fare.
(I never use YT whilst authenticated / logged in.)
I watch YouTube from Roku sometimes without signing in, but it still seems to somehow - by IP, presumably? - pick up related topics from searches on other devices (that are signed in).
Something we’ve noticed in our house is that if YT can’t figure out who is watching, it just uses the IP address. So I get recommendations based on what my kids watch, and my wife gets random recommendations for stuff based on what I watch.
I’ve tried the “Don’t recommend this” trick, but because the kids are subbed (or otherwise watch it), it still keeps coming back.