No, i get the trypophobia-triggering (DON'T GOOGLE THAT WORD) chumbox images when browsing in incognito mode, without pre-existing cookies or anything else. This has nothing to do with my ad bubble, https://theawl.com/a-complete-taxonomy-of-internet-chum-de0b... has mentioned that the chumboxes very often carry those images.
Totally anecdotal, but I think I see worse stuff in incognito mode than otherwise. Perhaps the default is bad, but with tracking you can get into a less bad bubble?