Concerning the "prejudice" against sim pilots the problem is IMHO not so much any firmly ingrained bad habits as indeed entering real flying with a "Since I have hundreds of MSFS hours and passed all virtual exams, surely I am a hotshot expert pilot in RL as well"
mindset as pointed out by P.A.. And for all its weaknesses, don't forget that sim-flying may have been the starter drug for some (e.g., me
Granted, it's useless for learning or practising airplane handling, but apart from spending delightful hours going to places I could not afford to visit in real life (and without all the hassle of actual travel), in planes I could even less afford in real life, (online) armchairflying has benefited my modest skills in several areas, e.g.:
- considerably improved nav skills (starting from a very low baseline, though: according to my instructor I had the rare talent of getting lost in the traffic pattern), partly from practising, partly simply from getting a better feel for how the surroundings look from above and how maps translate into actual terrain;
- being very much at ease with VOR navigation;
- better feel for time and distances when flying;
- improved R/T fluency and proficiency, including VFR and IFR phraseology and procedures when flying from/to controlled airports (and including R/T in French);
- a sketchy grasp of the sometimes fundamentally different modi operandi for different types of airplane;
- a somewhat better feel for weather and terrain considerations;
- several harmless but humbling and quite insightful experiences of hopelessly getting behind the course of things and how quickly this leads to errors and omissions.