It's not impossible, and searching through Unreal Engine docs would yield this result: https://docs.unrealengine.com/en-US/Engine/Rendering/Materials/HowTo/RadialMotionBlur/index.html I don't want to see posts with "It's impossible to do in Unreal Engine" because it's simply not true. Thank you for your consideration.
Control+F2 on a keyboard motion blur is nearly completely removed, if on console just plug in a USB keyboard and your good to go.
I'm well versed in the multiple methods one can employ to disable Motion Blur. Why would DTG spend development resources in the first place implementing Motion Blur just so users would have to turn it off? How else can you convey the sensation of speed to the player across what is essentially a 2d plane (your monitor)?
Dovetail have said themselves that the game engine doesn't like spinning circles at high speeds and has trouble keeping up with the wheels in game so it can get a bit blurry and poo. I'm no expert or have any technical computer skills so i can only go on what they have said themselves in the streams.
I’m sure there are multiple ways to deal with the issue but how resource intensive they are is probably the biggest concern because trains have many many wheels and TSW operates on the high limit of available resources. I’m sure it has been looked into in depth by the devs. How many things they have tried is only known by them, and they may have tried the method you have linked to already. It is true that the wheels look awful (they don’t look amazing with motion blur off either) and it is true that they somehow need to make them look better when motion blur is on (it does well at covering up a number of other artefacts of high speed train animation) but being able to perfectly animate a wheel in isolation isn’t the same as animating hundreds of wheels in a game where there is so much more going on and masses of complicated physics behind the scenes, so that particular solution may not be suitable with the resources left over for wheel animation in TSW. I'm not saying it is or isn’t I’m just saying it might not be.
Then why is their go-to answer "It's impossible in Unreal"? It is possible, and it is doable. Yes, I agree, the amount of work would be somewhat relevant, however train wheels is something that is standard between wagons and trains. What I mean is, for a train, you only need to do one wheel, and than duplicate it. Same for carriages/wagons/cars. Again, I would understand if their answer was "We looked at it, and it's not feasible", but it's not, theirs is the above answer which bothers me because it's just not true.
