As per the regulations
• Online Qualification begins on 10th September 2019 and end on 25th November 2019
• Open to competitors on Xbox One, PlayStation 4 or PC.
• Two separate competitions for Rally and Rallycross.
• Must be aged over 18 to participate.
• Setups for are fixed for online qualification.
and terms and conditions
9) A Driver is only eligible to participate in the Online Qualification if they have:
a) an Xbox One, Xbox One S, Xbox One X, PS4, PS4 Pro or suitable Windows PC; b) Xbox Live Gold Membership or PSN Membership (or such other online membership relevant to their platform and which is required for them to play online); c) the DiRT Rally 2.0 game (updated to the latest version of the Game publicly available on the relevant platform at the time they participate in Online Qualification); and d) an Internet connection.
10) Drivers are responsible for their
It seems oculus isn't on a PC, or at least it ceases to be a PC once an oculus headset is attached
I expected as much given the lack of clarity throughout regarding the oculus version.
I believe the announcement does mention Steam, its just unfortunate that the documentation isn't consistent with that.