Yes, a lot of people are doing their own conversions so they can get what they want, and leave stuff they don’t want or need out.
Sales number on first post doesn’t include these home built camper vans. I’m not sure there is a way to track numbers, but I’d guess it may even be higher than factory-built units.
If I had more free time, I’d give DIY a try. Sounds fun.
Mostly I like really simple stuff, and they don’t build much like that anymore.