Perhaps there are sites that failed because they removed comment sections, but I am not aware of any. (And it would take a lot to show it was the comment section removal itself that did so, as opposed to poor management, editing, etc.)
The precious way comment sections are viewed as a kind of right – by site owners and commenters – needs to change. At best, they should be heavily moderated and shut off without apology, viewed as gifts; at worst (?) removed altogether. No one is shutting off every open blogging platform and internet forum in the world where commenters are free to take their opinions.
It’s about time we combated entitlement by prioritising safety, solidarity and quality (as places like CreepyPMs do) over so-called “free speech”, that benefits only the loudest and usually most vile.
Or you know: shut them off altogether.