Ever since the update released, DMZ has felt significantly more smooth than before, it's less laggy for me now and now I can see the radiation circle.
Now I still have render issues and there are no train visible on the map, but I'll glady trade the train for a smother gameplay. I've also been pulling more kills now and completely stopped using the Echo shotgun, switching to a legendary Bizon. Once I almost killed a full squad, but the last guy got me with the Echo.
And here's an image of me taking the final helicopter, the soundtrack 'Ace' came back and plays in the final countdown. (This one: https://youtu.be/L666obR7tbI?si=RJKUnPTTNvd3uYC3 )