I think it's weird that people think it's ok to judge someone based on whether they left home in their early 20's or not.
My area is extortionate. I was at uni, then got a job, and moved in with my boyfriends parents.
We could have moved out almost immediately and rented for the rest of our lives, but we stayed out and bought our own property last year. I was 30, my OH was 36. His mum has actually take it very badly with us moving out. We contributed to bills, bought our own food/toiletries etc and she struggled when we left because she feels lonely.
I would have picked this situation a million times over moving out in my early 20's and renting forever just to say I did it at an early age.
I never judged my partner for living with his parents either. Unfortunately, some people do actually have to work minimum wage jobs, and we did this, saving money whilst also enjoying our new relationship. It meant we didn't rush into a mortgage with the wrong person and things are falling into place so nicely now I feel incredibly lucky. Sure it would have been nice to have done everything a little earlier, but I'm grateful for everything we've had and done together and now have got 