Not suddenly bad, I've always hated these tags and think they're useless padding. Basically, the issue for me isn't the existence of a watermark tag, it's the existence of hyperspecific ones. If we distinguish a platform watermark from artist watermarks, I don't have an issue with that personally and wouldn't be opposed if a BUR rolled them into one. Such a tag would also be considerably futureproof and not need regular implications/otherwise.
That's basically my only issue. With my point being rooted in "tags are for searching", I do acknowledge and agree with the desire for negation and am not opposed to setting something up for that case. It's also reasonable to not roll every single type of watermark into one single tag because then that poisons its usage, so essentially the same as what I initially said but sans specifically the watermark tag and a new general "site" watermark tag instead. We already have sample watermark, having some more granular options for watermark by more major uses of it (artist, site, general watermarks) would be kind of nice.
I'm not offering up a strict dichotomy with my opinion. Except for how I firmly believe that having a tag per site's watermark is incredibly dumb, I'm cool with the rest. I just didn't really think about it from the angle of rolling them into a general tag so my BUR on the other topic nukes them rather than moving them all to a single tag. That might be a good proporsal to get rolling.