You're right that there's not a good reason to expect incentive to block people, a priori, even though it's vaguely plausible. I do expect that they would cert

You're right that there's not a good reason to expect incentive to block people, a priori, even though it's vaguely plausible. I do expect that they would certainly be accused that that's their motive whenever someone gets blocked unfairly, which could lead to some bad PR, notwithstanding whether that's what's actually going on.