Remember seeing it on tv and it looked incredible and very moving. Although with that said Corbyn is right it's essentially a pretty tribute that detracts from the issues of the first World War.
Both my grandfathers died young because of first world war injuries. My elder sister remembers them, and to her it's not about 'issues' it's simply remembrance. Talk about the issues by all means, they're important, but don't forget to some people the sadness is still real.