Jack99
Adventurer
It has a sidebar in the 4e MotP that boils down to 'demons and devils don't like each other, but there's absolutely nothing going on at the moment and the planes-spanning ideological genocide that was a central motivating conflict on the planes - that's all in the past and doesn't impact anything now and we won't devote any further space to it.' I think the phrase appears maybe 8 times in the entire text, including headers and two item names.
When I said "no Blood War", either I should have been more clear in the term, or you're a bit too easily offended. No Blood War isn't the same as "it doesn't exist", just the same as saying "no orcus" during early 2e wasn't the same as saying "orcus no longer exists in the game at all".
The Blood War gets mentioned as an inactive non-issue within the default cosmology.
Actually, the Blood War is mentioned in other places in the various releases, but you are correct that there has been no dedicated articles or even chapters to it, which of course stresses that it's not the most important part of the devil/demon schism.