No one disputes that it'll be a close game, but I think Plebe's point is that 40% shooting is actually not great for Oregon - their season average is .419. And making 5 per game is literally half their average of 9.9 treys per game. So if anything, Oregon under-relied on its outside game to beat MSU. You probably should expect far worse in a rematch. Indeed, only 18% of Oregon's points came from behind the arc. I don't think you can credibly say the trey is what beat you in Eugene.
Rather, I think Oregon is a matchup problem for MSU on MSU's defensive end because most of Oregon's inside offense runs through pick and rolls and cuts inside, and while Hebard certainly can and does execute classic post back-to-basket moves to score layups (which McCowan can very effectively shut down), she doesn't have to - she and Sabally can both shoot effectively from the high post, and Cazorla, Boley, and Ionescu are all very good at moving to the basket and then making a swift pass to an open post player as the defense collapses. McCowan is not especially mobile, and stopping the Oregon pick and roll depends more on your guards than on your posts, so the question is whether Howard (when she's at the high post), Danberry, and Holmes can disrupt around the elbow. Last time, they didn't - Danberry fouled out, Howard fouled out, Ionescu went for 17-17 from the line, and Cazorla went 6-6 from the line. So if anything I'd say Oregon's stellar FT% and the pick and roll action along the lanes is what killed you - their guards were able to get inside and draw contact, and your guards didn't do a very good job stopping them. A lot of that is the result of pick and rolls to get inside and force fouls on the shot.
Ionescu actually had a bad game against y'all - she went 5-19 - but she's knows how to draw contact going to the hoop from the lane, and McCowan isn't going to save you from that. If I were Vic, I wouldn't be worrying about Hebard's layups or Oregon's shots from beyond the arc - I'd be worried about guarding the lanes. That's where Oregon dominated you last game.