People seemed to like Google+ but a) nymwars lead to dangerous situations (although no less dangerous than Facebook's graph search) for people that don't want to reveal their real names but also b) the merging of accounts ruined some people's Youtube channels. Zuckerberg is so much of a control freak that I suspect (based on evidence I've vaguely heard, not just my own intuition) links to Google+ used to get deleted. It used to be the case people liked it but they "couldn't get their friends to use it". So yeah - in part, inertia; but also what if you linked it and nobody saw it in the feed?
I'm actively avoiding Shorts, Reels, and whatever else with those mechanics precisely because they pull you in and snap an hour is gone with nothing of value to show for it. It's so totally different from regular long form videos.
We regulate addictive substances too, even for adults and without relying on parents. The amount of productivity and quality of life lost to these platforms must be staggering in aggregation.