I suspect this is the key. The RAD tools made application developers more productive, but they came with a downside. If the tool became popular, the vendor lock-in kicked in and it became expensive or the company maintaining it stopped doing a proper job of supporting of it.
Therefore, in the 90s, people became tired of this and looked for ways out of the vendor lock-in. That's why OSS started to get traction, and also Java. It turned out that it is cheaper to develop your business app in Java from scratch, rather than in a commercial RAD tool and then pay up your nose to a disinterested company for maintaining the base on which it stands.
So I think OSS is actually less productive and less polished than it could be (many of the RAD tools are actually really cool, but insanely expensive), but it is still case of worse is better.
I think it's possible that some business DSLs (which are at the core of the RAD tools) will win mindshare again, but it is going to be quite difficult.
(I work in mainframes and there is quite a bit of RAD tools that were pretty good in the 80s, when mainframe was a goto choice for large business apps.)
Therefore, in the 90s, people became tired of this and looked for ways out of the vendor lock-in. That's why OSS started to get traction, and also Java. It turned out that it is cheaper to develop your business app in Java from scratch, rather than in a commercial RAD tool and then pay up your nose to a disinterested company for maintaining the base on which it stands.
So I think OSS is actually less productive and less polished than it could be (many of the RAD tools are actually really cool, but insanely expensive), but it is still case of worse is better.
I think it's possible that some business DSLs (which are at the core of the RAD tools) will win mindshare again, but it is going to be quite difficult.
(I work in mainframes and there is quite a bit of RAD tools that were pretty good in the 80s, when mainframe was a goto choice for large business apps.)