I don't think much has changed. You're right that QB supply and demand play into it. In addition, the perceived talent of the QBs plays into it. Andrew Luck and RG3 were both considered generational talents. Snead leveraged that into an unprecedented haul. That trade is on several lists as one of the most lopsided of all time. That's not the normal #6 to #2 trade.
I'm fine if the Rams agree with you and don't feel that Mendoza or Simpson are worth moving up for. In that case, maybe there's someone later in the first they'd be sold on or try to accumulate 2027 draft capital.
Dart went #25 precisely because it was a weak top rated QB draft class. You're telling me that 2027 is a strong top rated QB draft class. If that's the case, it would be a mistake to assume they'll last to late in the 1st. Typically, in strong QB classes, the perceived elite types are gone in the first 15 picks. Supply and demand pushes the perceived elite types up the draft board.
What I know judging from the last 15 years of history, QBs selected from 16-32 have 20% odds of being with their drafted team long-term. 6-15 is 40% odds. 1-5 is 60% odds. My position is, align strategy with the odds, not against them. Most likely you will need a top 15 pick to simply have coin flip odds of finding a QBotF. If you get better odds from luck, great! But don't plan on that.