You're doing good work, and it's largely thankless, I'm sorry. 🙇🏽‍♂️

From my perspective, someone declaring being familiar with and trusting a youtuber when posting their link does not appear to provide a terribly useful function, or add any positive signals.

To elaborate; If I am unfamiliar with a poster, their opinion is practically irrelevant, as I do not know their level of competency in the subject they are posting, their critical thinking ability, their research skills, nor their biases. If I find the subject interesting enough to click, I will still need to determine its merit through my own analysis.

If I am already familiar with a poster themselves and they have shown a history of posting good quality links, then declaring they trust a specific youtuber is now irrelevant for me, since I can already assume the poster is continuing their trend of sharing high quality information.

If someone added "I know this youtuber, he's legit" to their post body, and that altered my perception of whether the video is worth watching or how on-guard I need to be with the information presented without being familiar with the poster at all, then that would, in my opinion, just indicate that I am susceptible to the power of suggestion. You would ultimately still need to determine the worth of the argument on your own, or defer to someone else doing that legwork, if they take the time to present a compelling case.

I do not think it unreasonable to expect others to determine for themselves the merits of a link I post.

I do think it unreasonable to expect someone to do a deep dive on every source referenced in a video and present their findings to a perspective watcher. If that was the standard we adopted here, it would absolutely have a chilling effect on people's incentive or inclination to post anything at all.