the reason there are only 5% of seats is most schools don’t think BSMD programs don’t have a real purpose and lot of them discontinued. Some are continuing for various reasons.
There are 25+ BSMD programs and you quoted 4 schools (probably forgot WashU). Most of them are not T20 (including Brown). I consider Nortwestern, UPitt, Baylor and WashU as the top medical schools among the BSMD programs and combined I believe they take less than 50 each year.
Anyone who thinks going to any particular UG school automatically gets them into equally or more prestigious school are hallucinating and there is no point in preaching to them.
Anyway, as long you don’t use “prestige obsessed” I don’t attribute motives 