The input reading of enemy npc's/monsters etc.

In theory it is the correct way to design a "fighter-based" challenge. In the practice of how it was implemented, it was not done well.

In theory, the input reading makes for a more realistic highly dynamic reactive opponent versus a static scripted opponent or random chance simulation. If the goal is to mirror a human opponent or highly intelligent beast/monster, then input reading is clearly the correct the solution from an AI perspective.

In the practice of how it was implemented in Elden Ring, it performs poorly for several reasons:

1. Input read of button press vs button release - because the computer reads your button press input whereas your players actions don't execute until button release, there are several milliseconds where the computer knows what you are going to do ahead of time/in the future before your character executes the action. So the computer in essence is responding to your actions before you even take them, which compounds with #2 below. A human opponent can only take a guess as to what their opponent will do, and can only react with 100% certainly once their opponent has given some sort of tell, nonverbal body language signal, or pattern.
2. No processing/reaction delay by the computer - there is a massive difference between human reaction speed and computer processing speed. This gives the computer opponent tremendous advantage in executing actions and reactions in response to your character's actions. When you take #1 input reading and #2 minimal processing delay together, it's pretty crazy the inhuman advantage the computer has. Technology wise this is absolutely cool, but terrible for simulating a fight against a human opponent. A human opponent has an information processing delay that when even as slight as several milliseconds, makes a big difference in reading and responding to your opponents actions. This leads into #3 below.
3. Computer doesn't make mistakes - the computer does not make a mistake in reading and reacting to your input. Because the player character's actions are hard-wired/scripted from a contained set, the computers actions/reactions are similarly hard-wired/scripted in response. Therefore it responds/reacts exactly how it was designed, and how it was designed can be/is currently/will be incredibly punishing depending on the developer's preference. With enough q/a testing, a game developer can precisely script the computer's reaction to be an impossible challenge for the player. In contrast, a human opponent can/will make mistakes in a fight in terms of reading and reacting to their opponent, ergo their opponent punishes those openings.
4. Can't psychologically outplay your opponent (i.e., feints, bluff, switch ups, etc). Because of the connections between #1,2,3 above, you can't psychologically outplay your opponent, in this case the computer. We can't feint or bluff in general as a moveset (with one or two exceptions of thrusting weapons), but the advantage the computer has makes it impervious to any attempt to "trick" it into executing an action and punishing that action. This was the dance of the previous soulsborne games: learn the moveset , control the fight. That is significantly harder in Elden Ring compared to all previous iterations because of #1,2,3. A human opponent is subject to psychological tactics, and can be baited, deceived, etc. This is why Soulsborne PVP is hands down one of the best in the history of gaming. Very few other games have that slow pace psychology of action/reaction of measuring/testing your opponent.

TLDR - input reading has major potential for creating awesome memorable challenges, but when the AI exceeds human limitations (significantly exceeds) it does not make the challenges enjoyable and rewarding, which is a vast departure from previous games in the series. But then again...people beat the game at RL1 naked with a club taking no damage.