Translation:It is too late to continue this conversation.
"Il est trop tard" is impersonal = it is too late
"Il est trop en retard" has a real subject = he is too late.
"Il est trop en retard pour continuer cette conversation" means that the man does not have enough time left to keep talking.
"Il est trop tard pour continuer cette conversation" means that this late hour of the day, the people involved in the conversation should stop talking.
Shouldn't "C'est" be used here instead, since the adverb (tard) is modified (by trop)? Or does the rest of the sentence change the ruling? I recently read an article on "C'est" vs "Il est", and this exact phrasing was covered.
Thanks for any help!