He shouldn't have been sent off but the criticism should be about the quality of refereeing.
Refs should focus on what happened rather than the (in this case unfortunate) outcome.
Last Monday we had a stonewall pen refused in the 93rd minute when the score was 0 - 0 and the pundits said they understood why the ref didn't give it "because it was so late in the game" - as if that's got anything to do with making the right decision.
Folk complain about VAR but at least it gives bad refs more information/less to hide behind and as in the case of the Leeds Liverpool game, teams should be given say 3 chances to question the decision as they are in e.g. cricket. IMO