Yes. If this happened in Australia, they might say, at worst, the rest of preseason. If this happened in Australia, you think he'd get 6 games (4 preseason + 2 regular)?
Yes. A player that throws a cheap shot in preseason should be punished just as much as the regular season just as much as they should be punished in postseason. This "games that matter more get less of a punishment" is bullshit, because the recipient of a headbutt, spear, knee, etc feels the effect during postseason play. What kind of f***ing joke punishes something for 1 game, because playoff games mean more?
There was literally a video of Doughty getting a knee and having there be no suspension. If the roles were reversed and someone was punished for just preseason, sure I'd be pissed. But I wouldn't think it was unfair. I would want the league to start punishing this behavior more consistently. I don't think they are going to suspend future knees four games the same way they did to Kaliyev though. Not because of an inherent league bias, but because of explicit incompetency by the Department of Player Safety.
If all knees of this caliber get a 4-game suspension, no complaint from me. But they won't. And THAT'S the biggest problem. I still think, kneeing penalties considered, this one is tame and not worthy of a suspension based on the history of suspensions levied.
Pre-, regular, and postseason all serve different functionalities, but they should all be treated the same as far as value. I bet you'd see some dirty shit drop pretty quick if players started getting 4 game suspensions in the playoffs.