Of course! Many debaters say exactly that, and judges are sympathetic towards it.
It’s often more strategic (nobody seems to attempt arguing against critical theory) given you already know the judge is receptive towards your opponent’s ideology/line of reasoning.
I agree with most of your comment, though I do think that most people haven’t been exposed to good arguments for longtermism/utilitarianism in general—if they were I think most of them would at least find weak longtermism plausible.
Most people who disagree with longtermism probably do so because partisans on their side of the political spectrum disagree with longtermism for x reason, and they haven’t been exposed to a fair analysis of how longtermists resolve most of the complaints brought up. (i.e. I think people would give up some of their irrational intuitions of they fairly analyzed longtermism)