I know the prevailing sentiment for a long time in the privacy community has been "DAE Youtube bad?" though I have always thought that it is kinda overblown. Besides, I am using Firefox which is supposed to isolate tabs so they can't speak to each other, so I felt a small amount safer using Youtube.
You can take my post with a grain of salt since all I have are anecdotes, but can anyone else confirm encountering creepiness similar to my experiences:
-Typing anything in another window that is not my browser, sometimes these words seem like they get picked up by the Youtube suggestion algo and then boom, I get suggested videos based off of those keywords. Recent example, I was copypasting the words "trans" and "talking" over and over for some nerd spreadsheet I am making (read: not transgender purposes) and what do you know, transgender videos about "How to change your voice" start popping up in my feed. Please know I have zero interest in transgender politics/culture/anything, it is not something I have ever searched for or engaged in online. Possible that Youtube is reading my clipboard? Reading my keystrokes?
-Listening to an album via VLC, while Youtube is open in my browser. Suddenly, more tracks from that album start showing up in my suggested feed. Possible Youtube is reading the titles of other apps current open on my machine? (VLC changes its active title to the name of whatever file is currently open)
-Have a Discord channel open in another tab, people there start posting things I am uninterested in and don't click on, but lo and behold, videos related to those things start appearing my feed. Tbh, I am the most jaded about Discord's privacy security because there is probably a direct communications pipeline between the Discord and Youtube where they link accounts to each other, even creating shadow accounts similar to how Facebook does. So while not surprising... still at least a little bit creepy, yes?
edit: let me add a small bit of context. I use Youtube all the time as my personal version of Spotify. Adblock+Youtube still works for me and is very nice. So all of my Youtube video suggestions are always music related. If anything weird shows up in that feed (you know, not music-related stuff) it sticks out to me immediately.
edit2: thanks for the replies, even if you are disagreeing with me. I promise you I am not the person downvoting everyone lol.
Again, which applications had access to your clipboard and user files at that time? If any of the applications running on your computer was stealing your data and selling it for financial gain, Google would likely be buying it and obviously using it against you.
You also have to consider side-channels. Were you or your friends talking about that spreadsheet project via Discord or some other known abuser? Did you talk about it with a person in your room while daddy Google or Amazon were listening? (Alexa in the room, Google assistant on your phone etc.)
This might simply be expectation bias. You may have been shown such suggestions in the same pattern before and simply didn't notice because, contrary to the present, the topic wasn't on your mind and simply forgot about it because you're being shown irrelevant suggested topics all the time.
That's how "The Algo^TM^" works. Google gathers data on you directly through its applications, from 3rd parties selling data they stole from you and indirectly through the same process from people you associate with.
It's even possible that some data broker simply made up the fact that you're trans. Google could have then assumed it's true because you associate with trans people here. I could very well see that happen in an enshittified system such as Google.