I can switch my ISP from Verizon to AT&T or Comcast with a single phone call tomorrow. Apple is far more of a monopoly than the ISPs in my area. Should we regulate Apple as a public utility?
Also, just because one company offers a faster connection than another does not make it a monopoly. Whatever company that sells the fastest production car does not automatically have a monopoly on supplying automobiles. Choosing an ISP is more complex than simply finding the fastest speed. Price and customer service come to mind immediately as very important. And if all the ISPs offer speeds that are above your needs, speed might not even be a major factor in your decision.