The main reason that Frontier were able to develop for the Vive, but called a temporary halt to supporting "current" Oculus drivers was that the drivers are a moving target.
The HTC Vive uses Valve' Open VR SDK and Steamworks VR API. These are (as I understand it) feature complete, so are a goal Frontier could shoot for.
Oculus had drivers (0.5 and 0.6) which operated in two modes, Direct and Extended. Extended worked as a "second monitor" - this was the mode Elite and many other games used. Direct required any application to be written to pipe the display direct to the HMD, operating at a different refresh rate and without desktop compositing. Faster, but much harder to support as it requires a dedicated hardware display mode for your application.
Many games that did "support" Oculus, such as Dying Light and Alien: Isolation, as well as Elite, stopped working when Oculus dropped Extended mode from their drivers with the 0.7 version.
The CV1 did work with Elite using Valve's OpenVR (a forum member here, ghcannon has an engineering CV1) with the latest (0.8) drivers, but despite getting it working initially, Oculus issued new firmware for the CV1 and this broke the compatibility with OpenVR. So no working solution now. Oculus keeps moving the goal-posts for everyone.
Currently Oculus does not have release drivers. As of this morning the "current" development drivers and SDK are 0.8, still. With the hardware shipping in 24 days.
My view is that Frontier are doing the best they can under these circumstances.