Yes, when the hit is borderline and obvious, there's usually a response. But, this was a clean hit at center ice. He didn't run him into the boards, or clip him up high, or even jump into it, just put a heavy body into him. And, yes, MacKinnon was shaken up a little, but he didn't even go down. How much response does that even deserve in the first place? To any rational observer, the answer should be zero.
And typically, the guy getting jumped after a hit isn't the first one to actually engage and throw a punch. You know there's a huge difference between the typical retaliatory response to a questionable hit and Girard lightly pushing him in the back to try to get around him. Even if it's a mild gesture of rebuke, there's no acceptable reason for Rinaldo to turn and throw the punch as a response to the light push. And that's why he was suspended for doing it. He's the only one who did something wrong here, which makes blaming Girard, even in the slightest, a really bad take. It's like blaming someone for being in the wrong place to get hit by a drunk driver.
And, the fact that Rinaldo isn't smart enough to discern who is there before throwing punches supports my point that he's not the kind of guy who deserves another shot. He has been suspended for 25 games in his career, and only has 18 career goals in 370+ career games, never scoring more than 9 points in a season. Is there literally no one else who can fill that roster spot? Seriously?