@Pangloss points something that is actually backed up by statistics and I know people hate them because they're not applied contextually but we have a contextual position here.
McGinn does very little to progress the ball when he has it. His passing and dribbling don't contribute to our attack in a meaningful way. Pangloss has observed it, as have I and thats the reality. Now can you say the same thing for Marv, absolutely but I dont think you can say the same for Luiz.
IMO Luiz and McGinn are about the same level but vastly different skillsets. Sanson will eventually show his quality as well Ramsey.
I love McGinn, he is excellent for 70% of matches because we absolutely need his battle but when you're 0-0 or 0-1 down against Burnley, Sheffield or Palace he's going to do absolutely nothing. I think its a two fold issue (a) he is playing a different role and (b) the man is clearly not in form and/or is fatigued. I genuinely feel any of our midfielders could have contributed as much or more than him in the last 6 games.