I think different rules apply for the Maguire and McTominay bids. I 100% support rejecting the McTominay bid; with players like Rice and Enzo going for 100mil, Scott is worth at least 40 as an international in his mid-20's.
Maguire is a different story. We're talking about a player the wrong side of 30, out of form, just stripped of the captaincy, and suffering regular online ridicule. His stock has never been lower, and West Ham are the only buyer. I think it's very risky turning down a 30mil bid. Maybe we get the extra 5mil we want, in which case great, and overall I applaud the club for trying to change our selling practices to avoid buyers taking the piss. But if there was ever a player where it made sense just to cut our losses, it's Maguire.