I agree 2/3 is unlikely, but I honestly think the only names that will win the Norris in the next 3 years are either Hedman, Josi, Makar, Fox, or McAvoy. (Seider + Dahlin has an outside chance as well).
There are a lot of talented young defenseman right now but not many Norris level defenseman. Compare this to a decade ago you had Weber, Suter, Keith, Subban, Karlsson, Chara, Letang, Pietrangelo, Doughty, Giordano, Burns, etc. who were all Norris caliber defensemen.
I do think plenty of names like Hughes, Heiskanen, etc. can start to build a reputation of being Norris caliber, but they aren't there yet.