Based on a few years of leisure experience with both PC sim and actual flying, my conclusion is that PC sim flying is potentially useful for the "headwork" part (procedures, checklist discipline, understanding principles of flight, even R/T if flying online, and navigation if you have a decent scenery pack). For the "airwork" part, its value is very limited IMHO. It is fun, immersive, and delightfully cheap, weather-independent and hassle-free (as soon as you got a running system, not immediately obvious with MSFS), but in my experience there is no appreciable aircraft handling skill transfer to real-life flying.