I could have swore that back when they announced the SRDs being moved to CC they were going to release all previous editions with their own SRDs to it as well.
I was preparing to purchase a number of TTRPG books in the next two months but after a long look at the possible increase I have sadly determined to only pick up just a few of them currently trying to make a list of my top three...
Despite the rigamarole I am eyeballing the Savage Pathfinder system more and more and will see if my friends will let me in if they run another AP in it.
As far as I am aware it hasn't been, a few friends of mine love it and I didn't really see many complaints online about it beyond people wanting original content for it.
Not sure about how Arthurian mythos isn't still popular, there is still new series and books and such being published and plenty of people online I see talk about trying to rework other systems (typically D&D into systems that do Arthur and his knights (usually unaware Pendragon even exists sadly).
Just a heads up, those Basic Fantasy RPG adventures aren't new, they've been around for some time, they are just now updated for BFRPG 4e it seems. Also, if you go to the BFRPG website they have A LOT MORE stuff for free in PDF format.