Yes. This just began today, even though I've had watch history off for a long time, such a long time that I don't recall turning it off.
Out of curiosity, I briefly turned watch history back on and "Home" (the YouTube page that shows a mix of content you've viewed and content YT hopes you will view) returned to normal. Then I switched it back off, reloaded "Home" and got a blank page with a plea to enable watch history.
It seems as though YouTube tracks and records users' activity on the site regardless of whether or not they assent to having their watch history recorded, but wants users to explicitly assent to being tracked and having their activity recorded before YT will provide their (marginally useful in my experience) 'personalized recommendations'.
Out of curiosity, I briefly turned watch history back on and "Home" (the YouTube page that shows a mix of content you've viewed and content YT hopes you will view) returned to normal. Then I switched it back off, reloaded "Home" and got a blank page with a plea to enable watch history.
It seems as though YouTube tracks and records users' activity on the site regardless of whether or not they assent to having their watch history recorded, but wants users to explicitly assent to being tracked and having their activity recorded before YT will provide their (marginally useful in my experience) 'personalized recommendations'.