Honestly, this is 100% foul on Tomiasu, and the only reason it was not given is that he stayed on his feet as long as possible. This is not the first time we’ve seen that, instead of rewarding this behaviour, the referees punish it by not giving fouls and then VAR doesn’t overrule them because they are not classified as obvious mistakes…
Footballs always kind of had the unofficial rule that if you don’t go down you’re almost asking for the advantage. Its rubbish, but its also a slight difference between a dive and going down, there has to be contact for the 2nd.
Now with VAR its significantly worse. You not only need to go down, you then need to scream and shout. The best example of this for me was the Man City penalty v Man United. Rodri gets an arm across the chest, goes down, then screams at the ref like he was just punched in the face. This is the way to guarantee a review on a challenge that is so often just seen as part of football.