For me it's the community. I joined a virtual airline (flywoh.com) 20 years ago. This was founded at the time by a 14-year-old who is now a manager in a real airline. Several real pilots have emerged from it and we benefit from their knowledge because they have remained loyal to us. Our motto has always been to pick up the pilots where they are. When you can fly from A to B, that's enough for now. The community will make sure that you get better and better. Nowadays we do this on Discord with live streaming. When you need help, someone will be there to help you.
I know that many virtual airlines want to be as real as possible. But I think that's the wrong approach. It's about getting better and better together with others, learning from others in a community. Without a virtual airline, everyone flies for themselves. I am still learning from our "real" pilots ;-) That makes the difference!