Perhaps they're demotivated by the reality that, more often than not, size matters.

Definitely not, because that is a factor that has always existed. In fact, it has never been as easy to grow as it is today. Okay, not since today, but since the SC "ruled" with its teams. And the fact that this is more or less a monopoly, for whose attention many users will do anything (in addition to conspicuous ass-kissing, also criminal/fraud) is frustrating. It is pointless to explain how it was "before". Today it is different. That is a fact. And it will stay that way as long as there are only "a handful" of normal users who believe in the power of the community. In any case, very few people who only got to know Steemit after 2020 can understand it.