Canucks beat the Predators in every game and won their series too. Regular season head-to-head match-ups don't mean a whole lot for the playoffs. The thing is, it seems to be a straw man argument being thrown around in the media. No one that matters is arguing that because the Canucks swept the Oilers in the regular season that means they'll beat the Oilers in the playoffs. It's just a talking point because most pundits don't have the capability(and in fairness, time) of digging deeper into a series and analyzing tactics, counter-moves, and specific match-ups.
It's a stupid headline just to create a story. Honestly, it means nothing. Even if it did, it still wouldn't mean anything in this specific matchup.
Oilers were absolute hot garbage of a team when Canucks beat them the first 3 times. Canucks easily wrecked them when just about any other team in the league would have as well. Then their last meeting, they didn't have McDavid.
Only an absolute homer would make a comparable comparison saying it's a wash because Demko wasn't there either. DeSmith actually played a great game, one that Demko would have provided little to improve. McDavid would have made that game a lot different, no way denying it if you're honest. Losing him would be like losing at least Quinn Hughes on the Canucks team.
So point is, this has been an untested matchup, one that has little bearing on the 4 regular season games.