The delta is a 1st round pick for Micah vs a late round pick for Ridder..... or also a mid round pick for a running back with a shorter shelf life vs a quarterback who doesn't take nearly the hits.
Of course it is an individual decision, but I think this year has proven with Pickett and Ridder that a quarterback projected in the mid/later rounds can increase their draft stock by sticking around another year, especially if they are on a good team where they can expect success.