Pogba has missed more than the one game. And yes, Pogba is just one midfielder, but he is THE midfielder. The rest are much of a muchness, so we could easily lose two or three of the other mids and be better off, as long as we have enough ‘bodies’ left. And Martial is the main centre forward. Losing the two of them, given how weak the squad is, as you said, makes a huge difference.
Besides, we’re not losing games by several goals or anything. All of our games have one goal in it pretty much. Pogba and Martial make a big difference there.
And losing the two full backs shouldn’t be underestimated either tbh. I personally think Newcastle wouldn’t score if AWB was playing yesterday, for example. In that break away, their man was being chased 40 yards before he passed it wide, but nobody could make the tackle before the ball went wide. I think AWB would have.