This season has been the most frustrating on record for me (I've been playing for several years) because the new cards are generally so well designed, and I had a bunch of fun at first putting together some off-meta decks that could still be competitive. It's been disappointing to watch all of them run into the Mill buzzsaw, which feels like every other match on average in rank 1-3. In my last match, I played a homebrew deck pretty well against a Mill opponent who made several misplays (I passed 1 turn just before they played ring of favor, lost R1 but went 3 cards up with carryover, and managed to pointslam quite effectively in a short R3 after I got milled) – and still lost to a late golden nekker.
Winning against Mill still isn't too hard if you tech specifically against it – I've found the most success with a double Kelly deck that's designed to push R1 at all costs and go 2-0, running my own ring of favor and a spores to counter theirs, and there are plenty of other counters – but it's just been a huge bummer to watch my other (much more wholesome) decks that might have a chance against anything but Mill sit unused in favor of a fairly standard and toxic Kelly deck. I finally got up to rank 1 and will probably be able to grind up to pro, but it's been unfun enough that I might just sit the rest of the season out :/ Fingers crossed for some mill-adjacent nerfs in the next patch.
Source: https://www.reddit.com/r/gwent/comments/u2bw30/opinion_the_prevalence_of_mill_isnt_a_problem/