While I will admit that all the types of events you mention do happen, taking trains into New York and using its subways often enough to know the difference between anecdotal experience and the usual and typical experience I’d say most of your examples are not what most passengers experience most of the time - I certainly do not. That said, do I agree there is plenty of room for improvement on the subways? Sure. As far as the fare, by today’s inflated dollar, the $2.75 fare to go absolutely any distance on the subway is a bargain.
Fortunately, I don't have to use the subway with any regularity these days. That said, it is a very rare trip indeed when I do NOT experience what I posted. There are ALWAYS beggars marching up the aisles of the subway car looking for handouts. There are frequently malodorous bums sleeping on a subway car seat and making sitting in that car impossible from the stink. The swingin' breakdancers are very common as well, and you can count on seeing beggars in the tunnels connecting lines. I don't know what lines you take, but I assure you that I see what I reported most of the time.