Depends on the absolute rate of false positives.
I, for example, am currently banned from Reddit, after something like 8 years of usage, due to writing a comment mentioning that Reddit administration was corrupt (how's that for irony? I fear the far-right may have been correct about Reddit administration).
In this case it is not a broken system but an actively malicious one but the point still stands: if it takes 8 years to get falsely banned, they still have plenty of active users at any given time, even high-value ones.