I don't think so. It would have to be limitted to utilities and feats that don't key off class features. That's a restrictive design requirement - I'd call it an 'issue.'
We've seen plenty of feat heavy articles before. We've also seen articles, like the recent one on gnomes, that included one power for each of a variety of classes.
Why is it hard to accept they could easily do the same thing with Essentials content? Have an article for Rogues with feats for various builds, some for the Artful Dodger, some for the Thief, some open to all rogues. With some new powers alongside new tricks.
It's just... we've seen
tons of articles like this already. But as soon as Essentials is mentioned, people don't think it can happen. I don't see why.
Indeed, in these very articles, we've seen the opposite - the Staff articles includes feats for divine characters, rogues, small characters, all of which can be taken by Non-Essentials characters. The lack of generic staff feats wasn't because they would have been impossible to add, but because the author of the article felt
they weren't needed, felt that the Tempest build plus Staff Expertise could already support staff fighters, and thus made a design decision not to include any.
The restrictions of Essentials vs Non-Essentials had nothing to do with it.
It's not that we're concluding that these articles prove that 4e is being abandonned in favor of Essentials. It's just that it was very clear, before, that supporting both the 4e and Essentials Fighter & Rogue builds would require a separate materials for each - because they were so mechancially distinct. The Pyromancer article, while cool (no ironic pun intented), illustrates that the same issue may well aflict all classes that get Essentials builds, even if they can (like the Mage) share powers with 4e builds. That indicates nothing about what the future will hold, it just illustrates the range of possibilities. It's not just the 4e martial builds and STR Cleric that theoretically might be 'orphanned' depending upon the game's future direction.
The Pyromancer article presents
an entirely new school for the Mage. That's very different from simply providing support for the Mage - you can easily have an article that presents powers that both the Mage and all earlier Wizard builds can make use of.
Again, I can see the concerns that articles will only support Essentials content, though I think that sort of judgement should probably wait until after the Essentials release is over. But claims that it isn't
possible to produce support for both Essentials and pre-Essentials material... there is no truth to that, and these articles certainly aren't proof for that sort of claim.