No, I think they shouldn't be double dipping. If I pay for premium I want no ads whatsoever. Not for the content creators to sneak some in anyway.

And no I don't tend to watch many with sponsor crap in them because they aren't actually very good (think the low-quality crap from LTT etc). The best channels (EEVBlog is one notable one) don't have sponsors at all because they're made for love.

What I am not doing is watching the sponsorship segments anyway. So yeah I use sponsorblock. And I use Ublock origin or revanced to remove the ads too because there's way too many now.