Is NVIDIA deliberately neglecting older GPUs?

Recently there's been quite some controversy on the web about the performance of NVIDIA's previous generation graphics cards like the GeForce GTX 780 series. For example, benchmarks in the newly released The Witcher 3 (as well as other GameWorks titles) reveal the GTX 780 is slower than the GeForce GTX 960 which is very odd.

As a result, there are quite some complaints from people who are angry about the lack of support for previous-generation cards like the Kepler lineup, as seen in this topic on the official GeForce forum. While it could be just an accidental driver snafu, some NVIDIA users even go as far as to claim that NVIDIA's recent driver releases deliberately crippled the performance of Kepler-based cards to make the new Maxwell parts shine as Kepler parts perform significantly worse with the newer driver releases.

In a response on Reddit, NVIDIA claims they're investigating the issue being reported on Witcher 3 with Kepler.