Of course people want you to write less when it means less work for them. But think of an academic review committee for a senior thesis. They aren’t going to heavily read your paper, just decide if it meets compliance standards for some preserved artifact for your graduation. But they can veto what you’ve written and send it back to someone else (your advisor likely) and have that person request edits.

So this puts the reviewer in a situation with misaligned incentives. They might prefer to tell you to prioritize concise communication, but believe the risk is high that such a thing will get vetoed by the committee for Dilberty reasons, and thus their feedback gets optimized for what the committee will superficially think.

When the committee is mostly attentive professors, this isn’t so bad and everybody is aligned on short, to-the-point style.

But my experience is that this is hardly true. Maybe one committee member will be an attentive technical authority, sometimes only your advisor. The others will be deans or directors of various sorts who view it as an administrative chore to even have to sign off, and probably farm that review out to grad students or adjuncts, who are far more likely to take a capricious point of view about e.g. heavy literature review or conclusion sections.