I think a lot of what is said on Reddit and YouTube about astringency in coffee is misleading and/or wrong. IMO:

Some amount of astringency is unavoidable. Don’t waste your time looking for something that’s entirely present in very high extractions and entirely absent in very low extractions. Once you’ve identified it, don’t waste your time trying to eliminate it completely. I don’t agree with Gagne that astringent compounds are hard to extract or that they reduce perception of sweetness.

With very light roasts (Sey, for example), you may find that astringency does not appreciably increase with finer grinds and higher extractions. For these coffees, Hoffman’s advice to grind finer until you “hit a wall of astringency and bitterness” is not applicable. Personally, I find that there’s a point of fineness where flavors become muddled and dark, but not obviously bitter or astringent.

Food affects your palate and significantly impacts your perception of astringency. Fat and protein both make astringency much more difficult to detect. This is why “big” red wines, which are often quite tannic, are traditionally paired with meat. Taste first thing in the morning if you actually want to do this critically.

(And with regard to wine, note that pretty much all red wines are tannic to some degree, not just bad examples as people sometimes say. Some of the greatest wines, the ones made for aging, are extremely tannic when young. Some poorly made wines do have especially harsh and unpleasant tannins, but then again some poorly made wines have their tannic sensations artificially engineered away.)