Alright, thank you for testing.
Yes it is possible. No one said it is not possible. It is possible if you use OBS and set it up correctly, it is also possible with some other recorders if you launch app and recorder in proper sequence (well that works sometimes, kinda randomly).
Let me paste part of my conversations with few youtubers who managed to record my game gameplay.
== Youtuber 1
He was not able to record the gameplay, still he didn't give up and ended up using a trick and record a video.
== Youtuber 2
This youtuber gave negative review on Steam after playing 0.1h (so 6 minutes).
Part of his review was
it's in Russian, but when you put it to Google Translator it's understandable. He says that the game is bugged and impossible to record.
I doubt he played those 6minutes. I believe he was trying to record the game and got simply frustrated so just left a negative review.
== Youtuber/Streamer 3
This one contacted me telling he has recording problems. I asked him to try to launch the app first and then the recording software.
I have more complaints on my emails somewhere. Those were just easy to find. I don't want to spend too much time searching for all of them now, but I think it's clear even with those few examples. After all I had several letsplay videos from few youtubers out of 69 youtubers who were willing to record the game. Those small unknown YT guys will spend some time to find out the way. But any bigger youtuber will obviously not bother at all as he has a long list of games in his queue.
So after all it is possible to record the gameplay, but not that easy with most of the recording software.
I hope that clears things out.