What is nice about the strokers, and this is from a weekend rider's viewpoint, is that after each ride you wash[if you want to] your bike, dry and lube the chain and leave it.
With a 4stroke[provided you do the same sort of riding than with the stroker] you have to change engine oil and filters very frequently, set shimming fairly regularly, worry about replacing timing chains, 4strokes tend to decent muddy slopes with great difficulty, trying to lock up the rear all the time, they make a sound that is unacceptable around a dinner table in polite company, yes they sound like a loud beerfart.
Even with a 4 and 2stroke of the same weight, the weight of the 4stroke is higher up, and that is a problem.