Yeah, one of the scariest but most important skills to learn in any fighting game is how to control the situation just by watching, waiting, and not pressing anything. I struggled with this for the better part of a decade before I finally understood how important that skill was to winning any fighting game.
And it is a very intimidating skill to learn because when you first start doing it, it means surrendering control of the match. You commit to some degree of inaction in order to observe, and that makes you vulnerable to people who might think less but act quicker. But you have to accept this risk if you really want to improve, because if you just act out of fear of the unknown, without information, just to try and break the suspense, then you won’t really be able to tell what’s going on in the match or your opponent’s head.
A good way to practice this skill in 2D fighters is to devote some matches to doing almost nothing on the ground and focusing almost entirely on anti-air. Doesn’t even have to be DPs or optimal punishes. Just focus your energy on making the opponent take some damage, any damage, every time they jump or otherwise take to the air.
When they land, focus only on not getting hit. Keep whatever range you need to make your anti-air work, and feel free to do big punishes on serious mistakes like blocked random DPs or supers. But don’t try to press the opponent to make something happen. Just watch what they do and react. Let them kill themselves by attacking you.
And after they get hit by your reaction anti-air, try and remember whether or not they change their behavior. (I know this is hard to do in the heat of the match. I still struggle with it myself.) Do they clam up and try to play defensively themselves? Do they stay overly aggressive but switch to a ground attack? Or do they just get tunnel vision and keep doing the same thing over and over until they die?
I would honestly say controlling space without hitting buttons – with the mere threat of your attack – is the most important concrete fighting game skill to develop by far. (The only ones more important are intangibles like attitude and critical thinking, which are important for life far beyond playing games.)
If you make this skill the foundation of your playstyle, whether you favor offense or defense, you can build a style that can beat any kind or level of player with enough practice and experience.