There are many things you can say about Witcher 3. It has many imperfections but at least as many positive qualities. However the notion, that the game's combat is a mindless arcadey clickfest in the vein of Ass Creed or the Batman games is just pure nonsense. Anyone repeating this bullshit here either didn't play the game or played it on easy. On the two highest difficulty levels, if you try mindlessly clicking during fights, most opponents will swiftly hand your ass back to you. Because most of them have some kind of a break action designed to counter you, if you spam fast attack. This can often leave you stunned and vulnerable, and will result in your swift death.
Many opponents can assume a defensive stance and block your attacks as long as they have Stamina remaining. Theoretically, you can wear them down by continually attacking and thus cause them to drop their defence. Theoretically, because most of the time, they'll counter-stun you before their stamina runs out. Some enemies are also quite skilful at dodging your attacks. If you go straight at them, you'll most probably miss and give them an easy hit opportunity. So yeah, anyone claiming they can just mindlessly click through any fight in the game, go ahead and try that against a succubus at the same level you are. The first one, that lasts 20 seconds and strips it of at least half of its HP, gets a beer.
And that's just fighting one opponent. Because unlike Ass Creed and other games like it, groups of enemies in Witcher 3 don't wait for you to deal with them one by one (if you agro them and then stand a few meters away from them, they may rush you or just wait and taunt you). They'll often attack you simultaneously and from all directions. Packs of animals are the best at this. If you encounter 5 or 6 wolves (around your level) and you let all of them get close to you, 3 out of 5 times you're fucked. One of them will try and attack you and the others will circle around you. Once one of them gets you and the hit animation plays, you are helpless if the others decide to attack in quick succession. Your full Vitality goes to 0 in seconds.
Obviously, I'm not saying Witcher 3 combat system is flawless. There are problems with it, like bad controls. I love it when in the middle of a duel Geralt decides to turn his back to the enemy and swing at a tree or a wall (don't even start me on the lock on feature). And fighting in confined spaces is almost impossible due to the fucked up camera. It is also true, that sometimes you can "stun lock" some opponents in a perpetual hit animation by spamming fast attack. But in my experience this is very rare (happened 3-4 times in the 70 hours I played so far.
So, yeah. If you want to claim Witcher 3 combat is a mindless button masher, go get that succubus. And remember to record it, so we can all laugh at you hard.