I still laugh everytime I read something like this. The basement kids and freesharders do it-but people saying paid professionals can't just tickles my funnybone for some reason.
That's a somewhat naive view on those things.
BS promises their players lots of things, which is a good thing. Just look at the meets & greets: "We'll have a look", "We're gonna fix that with an upcoming publish", "That's a good idea, we'll put it on the list.", etc...
Then they have their own new features. Taming revamp, maybe new expansion/booster or just a new story arc. Just check the publish release notes to get a picture.
We should also not forget recurring things like new vet rewards, in-game celebration activities for RL holidays, etc...
Of course they also have to fix bugs in between.
And everything has to work on both clients for both rulesets (or more i.e fel/tram/siege).
So with all that in mind you have to plan in advance to get everything in a publish. Those are relased every 3 months, so roughly planning 1 year ahead, which equates to 4 publishes sounds reasonable. Bottom line is, they are pretty much booked and they won't be bored, ever... because there's always the next upcoming publish.
And planning and managing such a project also means, that you have to scrap features and ideas which are not worth doing or maybe would be worth, but there are other things, which are more promising, which is also a reason to put things on the backburner or abandon them as a whole. They're running a business and there has to be some return of investment.
So "the devs can't do it" does not necessarily mean, they can't do it from a technical standpoint. 95% its just the lack of time, resources or both...
And what do the freesharders do? They set up the emulator and mod the client. Once they go live, the majority of work is most probably done and they won't rework certain mechanics or features anymore. And if they do, they can set up their own deadlines, if at all. And should they break something or delay things, well, they don't have paying customers, which would show up with forks and torches at their gate.