Really? I've used YouTube for years and i don't think I've ever seen a "show me something different" button. Occasionally it'll have a too bar with a list of topics i can choose from but it refuses to let me enter my own desired topic and seemingly only randomly shows me the bar anyway. I find myself frustrated that it's never there when i want it, and a selection that was there last time is not there this time. Very frustrating to see the potential of a better user experience but be refuted it for seemingly no reason.
If you're familiar with the YouTube homepage (where it displays videos in rows by topic) you can usually scroll down and find one of the cards a sort of colorful "Show me something different" card instead of a regular video card.
I putzed around with YouTube for a bit and was unable to get it to come up but it's a pretty rare thing to see - it's possible it was a limited time feature trial but it also just might require a lot of weird actions to summon. I swear I have seen it before and it wasn't just a fever dream though!
