Let me just say that in no way do I actually think Schofield was a dumbass. It’s a given that he was doing the best he could under difficult circumstances. Cinematically it was excellent, just not very interesting or well-written from a military point of view. That’s not the character or the actor’s fault.
Mrs R and I saw 1917 today. On the way home it occurred to me that if the movie had been made in the 1960s, Scofield would have been too late, and the whole regiment would have been slaughtered. If it had been made in the 1970s, Scofield would have arrived in time, but the commanding officer would have ignored him out of stupidity or sheer bloody-mindedness, and the whole regiment would have been slaughtered.
I suppose that the regiment is lucky the movie was made during one of the periods in which it would survive 
It was also nice to see Mark Strong playing a good guy.
I wonder if the difference is really due to a lack of cynicism on the part of today’s audiences rather than the way movies tell stories these days. I think a lot of movies these days (including this one) use a video game style of storytelling where satisfaction is doled out by each successive goal being reached. A happy ending or final victory is necessary to “finish the game”.