Genghis,
I started off in microlights.
I remember well the microlight people, some of whom were very responsible flyers but there were still a number who flew on the margin, didn't believe in radio's or transponders or ATC etc.
These days responsible flying is important. A PPL should be seen as a starting point and, apart from you, everyone else seems to agree that instrument training makes for a better and safer pilot.
When someone asks the question "should they have instrument training?" then most pilots would say it's the best thing to do in order to progress to be a better and safer pilot.
FF