You can agree with him but the precedent has been set, and it is clearly that any head butting motion is a direct red card. Not a shadow of a doubt that Gabriel should be red carded and suspended. Brutal decision from the wanker of a ref and VAR. Not to mention the yellow Gabriel should've had already for ripping Erling's shirt in half.
Not acceptable from the best league in the world. If the league wants to come out and announce that its now a yellow card offense if a player makes a stupid threatening head butt gesture but no contact is made, sure. IDGAF but it is just proper stupid for a player to do so when a red should be guarenteed. But that is not the rule, and he was let off the hook massively.