Looking at your set up as nice as it is, I am not sure how you fool yourself into believing you are actually in the car, regardless of resolution.
I am pretty sure at some point you just got into it and now do notice that you have three massive monitors with big gaps and you are sitting in a purple room with beige carpet.
If I were to try you set up for the first time, I could probably list a lot more reasons your current set up spoils the immersion than you listed for the headset.
In a similar way you are comparing the current VR headset I could suggest you get an actual car body frame and build the monitors into the windows.
I am however not a fan of car simulations and I guess that's why your mind makes the leap. I have project cars and if you got it for car simulators only can understand your points on resolution. Distance is still quite low resolution but for me the feeling of being there out weighs this.
Handbags at Twenty Paces ... who will flinch first !!!??? This is riveting stuff ladies 😛