That's not even a yellow for me.
Iran player leans on him and Ronaldo pushes him away, but that's not an active elbow to the head.
I've refrained from passing judgement because while I have ambivalent feelings about Ronaldo (I am a juventino, after all), I am clearly a fan of Portugal.
So I've questioned what I thought I saw. I tried to see an elbow. I did not. To see one there would have been extremely harsh, IMO. I saw two players banging into each other to gain advantage. One blocking the other to even the extent he leaned back into Ronaldo to interfere with him. And I saw a Ronaldo who was irritated -- but not petulant and pissy Ronaldo, which is different and always worth a red card -- and used his arms to reach around a player backing into him so he could attempt to get to the ball around him. Not so much to throw an elbow to cause physical harm, not so much an attempt to strike the player's head, it was more like a shove to get a guy coming at him out of the way.
But Hoori is right. The ref should have given a red or nothing, not some half-assed yellow that makes no sense. He hedged. I thought it was nothing.
@king Ale is right though, it's either nothing (which it is for me), or it's an elbow to the head, in that case it's a red. The yellow the ref gave seems kinda half assed.
My guess is he either thought it was nothing, but didn't want to give the impression to favour Ronaldo, so gave a yellow, or he thought it was a red, but didn't have he balls to send him off. Something like that.
That was my guess too.
Meh I still don't see that as much an argument against the necessity of VAR in the face of how terrible refereeing is in football and how, perhaps due to the low scoring nature of the sport, 1-2 bad referee decisions are changing the outcome of the whole tie.
The complaints of terrible refereeing in football is almost entirely from the perspective of TV viewers, and that irks me. It exalts the frame of reference of a glowing screen in a kitchen above any other perspective, and that's just wrong to me. Even if there are millions more of those perspectives, it turns over the judgement of truth at a football match into a remote viewer popularity contest like some kind of pop singer call-in reality TV show. Most people have no issue with that, but that does offend me.
Whether you like it or not VAR is coming. I understand that it does interrupt the flow of the game but so does any kind of extended stoppage and there are already plenty of those in football. Like I already mentioned, i'm pretty sure it isn't just television viewers who want this like you tried to frame it. I have heard almost no opposition to VAR from actual professional players, coaches, refs etc...if anything its the "fat slobs" watching on tv or former players that bitch about everything not being the same as when they played 30 years ago

The game evolves, fast too. Might as well get used to it.
A good point you make here is the players. But when I read quotes from the Serie A players last season, I'm not so sure the verdict was positive. I mean there's the issue of Italian referee bias that has cost Juve so dearly - so in that sense that's where VAR is practically required because the credibility of the sport is held more in a conspiratory regard rather than one of human accident or natural observational error.
Maaaaan we were so close
It was one of the weirdest things. Note that before the match I had picked Portugal and Iran to draw 1-1 -- I expected Portugal to do the lazy thing and just enough to go through second to Spain. But seeing the Iran fans at the stadium, knowing what a big deal it was for the women in Iran to attend stadium matches, I could palpably sense how much even just getting a goal would mean to them. Given that even their only goal thus far was effectively scored by Morocco. And knowing Portugal would still go through on a draw, I was actually kind of rooting for Iran to score the penalty. It was weird.
But don't kid yourself, Hoori. Iran was really never in this match. I'm not saying that as some kind of value judgement or diss. Just that the outcome was really in little doubt throughout. And even the wackiness in the end would have been a complete fluke if somehow that could have been on goal and Patricio would have missed that. It wasn't as nearly as close of a chance as I think the nation wanted to believe.