My guess is he was concerned about there being a run on OT's so didn't want to trade down and miss out.
Gutekunst said he had multiple options to trade back from No. 25, both to later in the first round and out of it entirely, and that he realized early in the night that he wouldn’t trade up because several players the Packers identified as trade-up targets didn’t fall far enough. With Morgan still available and where the Packers would’ve traded back to, Gutekunst didn’t feel comfortable retreating and instead grabbed his guy, sticking with one first-round pick at his original spot for only the second time in seven drafts as general manager.