Some fans are devastated that Xbox One mod storage is bigger than that of PS4's. The release of 'Skyrim' Special Edition mods has also been met with mixed reactions. The release date of 'Skyrim' Special Edition and its mods has since come and gone, but Bethesda has not updated fans on PS4 mods for 'Fallout 4.' It was previously noted that the PS4 mods for 'Fallout 4' will drop after 'Skyrim' Special Edition mods arrive. However, the delay is apparently due to the developer making sure that mods will function the same way across all consoles. This is understandable since Bethesda was unable to fulfill a promise they had given. This was met with outrage from fans when it was first announced. However, the release date for PS4 mods have since been delayed indefinitely. It can be recalled that Xbox One mods were released earlier in the year, with Bethesda promising that PlayStation 4 mods would arrive a month later.
Whether it will change in the future, I don't know. This much was revealed when Hines responded to a fan's tweet. However, it seems that there are a lot of moving parts preventing it from being approved.
According to Bethesda marketing vice president Pete Hines, mod support for PlayStation 4 has apparently already been done.