Setting aside stuff like insurance issues, I think the answer will depend on what you ultimately want to do.
The PPL training business simply assumes the punter is probably going to drop out ASAP, and the few that stay will just do burger runs.
So it makes sense to train in spamcans.
The more keen and better funded people who want to do e.g. serious flying around Europe and want to buy their own plane are discouraged, because the instructors know almost nothing about the subject and because they want to keep him soing self fly hire for as long as possible.
Let's say your objective is to get an IR and do European touring. (Touring beyond Europe is a hassle, relatively, due to corruption, fuel issues, overflight permits, etc). Wouldn't it make sense to get yourself trained in a plane which at least resembles what you will ultimately be flying?
I gather that various air forces have stopped SE spamcan training because it is just a waste of time.
Flying a more complex type requires a better intellectual grasp, but flying something with a G1000 also requires a better intellectual grasp...