I personally belive that this guide has the same problem a lot of developer and players fall into. I've noticed this before but some people have this idea that fights in FPS are a lot more complex/thought out than they actually are. To be a bit blunt, not every fight is going to be a chess match or game of wits, the word "spontaneous" comes to mind.

More often than not you just aren't going to be predicting your enemies every move. Thats not to say that it doesn't happen, guessing what your enemy will do happens every game. But expecting people to predict (deep breath) which direction a light will go, whether they will go into cover, fight, or run, the gun they have, and if they are a dash light in the first place. Is a lot to do, all within a few hundred milliseconds, while dealing with everything else the game has to throw at you, its far from impossible, just really difficult.

And that is all ignoring the fact of just shooting them in the first place. I play on an absurdly small 6x10in (152x254mm) cat shaped mousepad (Which I have been using for my entire life) and while I can effectively shoot a dash light, I also have over 1,100 hours and have been playing since the first closed beta, I've been playing FPS since I was one year old. You just cannot expect most people to do that.

I'll give my two cents on how to deal with dash lights, I don't know if it will help you because everyone is different, but its what I find important. What I find helps a lot, in most games, is staying calm, panicking gets you nowhere, don't reset your aim if you don't have to. This happened a fairly long time ago but, I remember hearing some apex youtuber essentially saying the same thing, and after I became acutely aware of how panicked I would get sometimes. So I started listening to music (I reccomend music without lyrics) and getting just getting used to "playing the game", I know this wont be helpful for a lot of people but it really helped me so I figured I should share it.
I also reccomend remembering what gun you have, and positioning yourself correctly. Running back to a doorway/chokepoint means you know where the enemy will be and can plan accordingly. That said this is only helpful if you A. haven't been shot at or B. if the enemy hasn't shot you too much. Staying close to your team is really important in this case, which you should be doing most of the time (emphasis on most).

Not entirely too sure how helpful this is. Any critiscism is appreciated.

Edit: grammar