By the way, as a mod author who has been keeping up with this and was invited to CK before release/etc. etc. let me shed some light on this situation:
I hate to say it, but these issues are 100% on Sony. The three primary problems with mods on PS4 were the following:
Limited space. 900MB total for all mods installed. It's less than half of what's on Xbox and last I heard they still plan to make Xbox's mod storage limit bigger in the future.
Audio. PS4 uses a proprietary format that the release version of the CK can't compile. Bethesda needed Sony to hook them up with tools to work with that format, permission to release what they used, or permission to make it so the CK could save audio in that format.
Texture format. Again, PS4 uses a proprietary format for textures. Sony restricted texture distribution to the PC format. PS4/Fallout 4 on PS4 is not optimized to use the standard PC format, so it ate too much memory and diminished performance. Once again, Bethesda needed Sony to either hook them up with tools or agree to let them release what they used to save their textures in the PS4 format to the public.
The beta was cancelled/mods delayed because Bethesda was at a roadblock with Sony refusing to help. The way the post makes it sound is that Sony was ultimately not willing to play ball on this, therefore severely restricting mods and Bethesda didn't want to release mods like that. Would partial support be better than no support? I'd say probably, but that last bit is speculation on my part.
At any rate it's been no secret in the mod author community for months that Sony has been yanking them around about this. Sony assured them it was possible before they announced it, they announced it, then Sony wouldn't make it work. It's very unfortunate for everybody involved but no one more so than PS4 players who are being robbed of something great.