This technically useful skepticism can be weaponized against you by a rhetorical opponent by just pointing out that you "refuse to say for certain". All you have to do is say "some scientists believe there is some uncertainty" and you can convince a crowd to stop listening. Scientific communication works very poorly as mass communication.

Statements of certainty can be weaponized even more. That same rhetorical opponent would be just as happy to point out some exceedingly rare edge-case counter-example (no matter how dubious) and crucify the entire study (or worse, haul you in front of Congress and try to pepper you with "gotcha" questions in the hopes of catching you in a "lie" so they can make an example out of you). You rhetorical opponent is not going to argue in good faith either way and their audience are not people who will care.

Scientists write for other scientists who already know why they use the language they use. Compromising that language to try to cater to fools who couldn't care less about the truth would just make the scientist a greater fool for trying.

I doubt you're implying that scientists should "say for certain" even when they aren't certain, or that they shouldn't say anything at all. So I assume you're just saying "misleaders gonna mislead", which is true.

But as long as we're bringing up general social woes, I'll point out that those misleading statements are pretty tame by today's standards. The more popular strategy now is to just lie outright.