I've never played a turn-based game that isn't equivalent to playing chess where you know the AIs first 5 moves. It usually goes like this: you start a game not knowing any of the systems and at first. It's fun to figure out what works, but within a few hours you "crack" the game and it becomes braindead. Usually, the very first area in a game is the most difficult before you figure out what works and repeat it ad nauseum. Essentially you abuse the very predictable AI, and the actual tactical puzzles are very few.
They give you movement limitations as if the game ever truly takes advantage of them. Increasing difficulty only limits viable builds and game styles without doing much of anything to improve on the puzzles because the only real puzzle is builds and repeating the same tactic over and over once you figure it out.
Peak of gaming are games like doom eternal and dark souls series. Yes, the adventures in codex beloved games like fallout, bg2, etc... are great but the gameplay is basically witcher 3. You are all hypocrites. Nearly all the top 100 rpg codex games suffer exact same problem as Witcher 3 and just because the game is "turn-based" does not make it any less braindead. Instead of spamming left click, you spam the same "tactic" in turns as if it makes any meaningful difference.
I am sure turn-based games where every fight is a puzzle at every turn exists (like chess), I just haven't found it. I am not saying real time are much better (Witcher 3 says hello), but at least I've played quite a few well-designed gameplay loops in RT games. Perhaps forcing quick decision making in a real time fight makes for a much easier puzzle design set up for meaningful combat.
Cope in comments to your hearts content.