twitter's sins:

twitter committed many sins that hurt their ability to grow - maybe more so than the popular narratives.

One particular problem was the high Gini coefficient where
(a) certain people on the platform had huge followings (e.g being on the suggested list)
(b) the algo rewarded them with more followers

Good point. The reaching 1m users wasn’t so much of a deterrent because many can’t fathom that reach, but suggested list is an issue because this establishes your experience potentially for the life of product use. It takes effort to purge and restart after faulty follows.