That remains to be seen, but I doubt it.Essentials is going back over territory ALREADY COVERED BY 4E and making improved versions of what we had already.
Replace 'improved' with 'simplified' or maybe 'streamlined' and I'd agree.
Seeing how the essential classes seem to be less flexible than the similar builds we already know, I don't believe everyone will want to switch to the essential version.
I'm also not sure if the essential builds are really meant to replace the old builds. E.g. the 'knight' build sounds to me like it might be even more focused on defense than a sword & board fighter. I wouldn't be surprised if they got plate armor proficiency right from the start to replace on of the features a fighter normally gets.
All essential wizard builds seem to be similar to the specialist wizards of old. But what of the universalist wizards?
I don't believe the new builds will generally be considered to be an improved version of existing builds, even if they're covering similar ground.