Essentials is essentially 4.5e, only WotC also published free errata to update the 2008 books to the Essentials Standards.
But the class design is completely different, because the ideas about what the game was and how power sources and class features and combat vs out of combat worked. It’s as much a Change as 3.5e or 2e from 1e were.
And that’s the sort of shift we’re looking at now. Building on the framework of 5e but refining to the new audience.
I wouldn’t call it a new edition, but I also wouldn’t split Basic from OD&D and 1e AD&D, or BECMI from B/X from RC, or 2e from late 1e. The boundaries are fuzzy.
Publishing-wise, it comes down to whether they offer free errata for 2014 books to update the mechanical options to 2024, or if they assume we need to buy the new versions and just throw the old ones to Legacy Content on D&D Beyond.
If they’re requiring you to buy new books to be compatible, then it’s more likely a new edition. But they said it’s backward compatible, so if new adventures and options can be attached to 2014 books, it’s not really a new edition…