I'm fine with this, in fact an increase has been needed for a long time, and I think you'll find the vast majority of buyers will still either A) leave no feedback at all, or B) be succinct.

How do I know? Etsy has an 840 character limit for reviews, so if you want to see what having enough space to actually say something substantial results in, have a peek at some shops with thousands of comments. 

Yes, when someone wants to rant, it's a big, long "this person sucks because of A, B, C and then they D'ed!!!!", but that is more often a case of giving someone enough rope....IYKWIM. 

Lots of people get frustrated over there because unless you're on the app (where you can leave a star rating with no words), you can't leave a review unless you also write a minimum of 5 words and most people just wanna say thanks, or some short variant thereof, so I doubt we'll start seeing novellas appear on FB pages.