Again, 100% wrong. The #1 pick in the 2021 draft was signed for 2 million underslot. In the first round alone teams picked lower rated players to sign to lesser bonuses at the 1st, 3rd, 5th, 7th, 9th, 13th, 18th, 19th, 20th, 23rd, 24th, 26th, 27th, 28th, and 29th picks.
Also I know from the top of my head that the Mets punted on a ton of picks trying to make room for Rocker.
I mean if you don't believe me, pull up this list of draft picks and signings. In the 10th round alone there are FOUR players who signed for slot. 4!
In the 10th round the Sox signed their pick for 20k. In that same round 6 other teams signed their picks for less money, including the Dodgers, Padres, Twins, Cubs, Braves, Giants. Take a team like Tampa who signed a player for just 3k underslot in round 10. Their 9th round pick was signed for $17,600, or about 133k underslot.
Texas had a 2nd round pick signed for $830k, or $1.1 million underslot.
Houston had a 5th round pick signed for $47.5k or 300k+ underslot.
So yes, I don't know what your made up definition of "punt" is, but the Sox are exhibiting the same behavior as the other teams who are the most successful in the MLB draft.