This is close to the issue I have with him, tbh. And my answer is this.
Because that's usually the key decision/awareness that you need to have when you are the back-stick defensive player. Do I need to help my CBs? Am I able to help my CBs? Where's the opposition wing player who might come in on my blindside and get a jump on me because I've not got close enough to him early enough - which is my best chance of doing a very difficult thing and marking him out of connecting with a quality cross. Fortunately a lot of the wing players won't be big enough or that interested in competing for those headers either.
That's my reservation, that he doesn't, and can't do that. Although there was the 1 he defended well today, as you say, and 2 that he didn't from what I remember. It's picky because of how good he is going forward and how admirably competitive he is. On a good day, his competitiveness doesn't become a liability either but sometimes it does. It's the same with the defensive positioning issue.
As we said, he was 'done' on reputation alone last week by a f**kwit referee - referees are supposed to know better.
Both aspects are a does the good outweigh the bad (let's say less good, instead)? kinda question. You pays your money and takes your choice. I'm still slightly against I'm afraid.
But yes, he played well enough today.