This always gets a little heated, but you should buy what you're comfortable with. When we were first starting out, we bought a couple of used slide in Lance campers and then one new one the way we wanted it. We kept it 8 years and lost very little from what we paid new.
Our next coach was a Class C that was new and we kept 14 years. After the kids quit camping with us, we wanted to buy something more comfortable for two people, but new we would want a DP in another 5 years for retirement. We bought a used Class A for that interim period.
Our last two coaches we bought new because that's what we wanted and could afford.
I look at it this way, if you like new, can afford new, buy it, but don't criticize those who buy use. Those who buy used have their reasons and they also shouldn't tell others how to buy.