Are you writing this from experience? If so, is this from experience as a boss, as a low (maybe even average) performer, or a high performer? How do you know that your statement is true?
Not OP. But we all have different motivating factors each with their own level of efficacy.
As someone with ADHD (and who knows what else), I've found it very helpful to have some sort of colleague or peer or "boss"-type supervision or nudging, and I say this as a "high performer" if we want to use that term. This kind of motivation is almost non-existent in a WFH context as check ins and other such regular interactions are very high-pressure.
My point is that one cannot make blanket statements about "low performers performing better under supervision". I say this as someone who prefers to work from an office at least 4 days a week.
You're right, each of us have differing motivations. That doesn't give anyone license to promote their own point of view and tar everyone else with the same brush.
This comment isn't intended as an opinion on RTO, but one of the things that's helped me with ADHD has been to go for frequent walks after short bursts of work – I've actually thrived at remote work for that reason. We've all had to learn our own techniques to get our brains to cooperate with our goals.