I, personally, can’t handle having more than like 6 tabs open at a time (not including pinned tabs, which I can have 1 or 2 of at a time on top of that). It gets to where I actively close tabs to try to get my tab number closer to like 2 - 4, which is usually where i’m comfortable with.
Relative to my friends, I keep a lot of tabs open. But in this little corner of the internet filled with power users, I’m guessing I’m in good company and if anything, probably on the low side.
One of my friends works in a research-related industry, so I have this odd suspicion she’s slowly turning to the dark side as well. :)