All modalities of training, even those used within the tactical communities, are usually unrealistic in some way but applicable in another way. That is what gives it its value.
For example, in live fire training actual gun fire and handling skills are practiced and tested, making that part realistic, but human interaction is totally lacking. In scenario training with blue guns there is zero marksmanship and very little gunhandling but the element of human interaction is maximized.
This is sometimes brought up concerning dry practice or certain live fire drills. Racking the slide or thumb cocking the hammer may be needed to conduct the drill and the stated concern is this will build a training scar as the trainee might start breaking grip to rack slide in live fire too, and perhaps that one should just keep pressing the dead trigger. Of course, that might train one to fail to respond to a stoppage.
This is a silly argument because dry practice has huge benefits. Unless dryfiring is the only practice done this might be a problem (maybe) but when other practice is used, such as live fire, this overcomes the potential issues that could be ingrained by using one training modality or drill exclusively. Mix it up so you can get the benefits of different ways of training and different drills, and those varied benefits help override the inherent danger of bad habits.
The fact is you do actually want to create some habitual behaviors. Some things should just occur automatically should you find yourself unfortunate enough to be in a gunfight. Try to avoid instilling “bad” habits by focusing exclusively on very simple things, presentations from holster, focus on front sight, driving the weapon between targets, malfunction clearance, reloads, etc. Focus on basic, fundamental skills and polish them to ever-higher levels.