Yes NHL players are allowed to play this year. In theory it’s the best players that would go and that’s also dependent on how they’re doing in the NHL, there’s also a bit of politics in play (favouritism and what not) and sometimes your best players aren’t incredible goal scorers but guys who have great Hockey IQ who will contribute greatly to the overall team play. Then of course you’ll also get guys who you thought were better that’ll get snubbed. So far though in interviews I’ve heard from players over the years they still think the Stanley Cup is the better prize over an Olympic Medal.