I have not watched the tape on Lance, but a quick look has me agreeing with you. I could understand taking Mac at 12 or 15 when Fields/Lance are off the board. But trading two future first round picks for him? I guess one could have considered Denver/Carolina threats to take Mac Jones but if that were the case Philly's #6 pick was there for the taking at less of a cost.
There was some smoke about Atlanta being so infatuated with Lance that they will take him at 4. So, like you, I assumed to jumped to 3 to get Lance before Atlanta. He would thrive in SF. But the 49ers top brass did not even attend his Pro Day which would make it odd if they selected him. With Lawrence and Wilson going 1-2, who is there to smokescreen your intent to?