Starting to wonder how many people posting in this thread actually play poker.
a) this player may not be a pro, but that doesn't mean he's an idiot.
b) even $5 players understand that you can't raise for value if no worse hand will call. Jamming a flush or even 7s full here is idiotic because there's no worse hand that will ever call. So Morgan is always calling (or possibly folding) with those hands here, never raising.
c) Smirnov overbet the river. Morgan isn't going to see that massive overbet and think "oh, what a great spot to bluff!" It's a polarized bet and since it's going to be the quasi-nuts a lot of the time, Morgan is only raising here if he has something resembling the nuts himself. Sure, a pro with a straight flush blocker or something might figure out she needs to turn her hand into a bluff to win here, and make a crazy but perhaps amazing shove, but there's no way this nitty amateur is doing that.
d) Basically the only hands I can see Morgan getting to the river with here and raising on the end are JJ or Ts9s. I'd think the chances he had anything else are almost zero. In a vacuum, JJ is 3 times more likely than Ts9s, just counting combos. But if you factor in preflop and flop play, Smirnov might have reasons to heavily discount the likelihood of JJ here.
e) Someone asked why Morgan would shove a straight flush on the end? Are you serious? If you don't shove a straight flush against that huge overbet on the river, you shouldn't be playing poker.