It's why you cannot trust polls and the likes in authoritarian states. Even outside of state manipulation of numbers, when people are afraid to actually speak their mind, then it completely invalidates any sort of results you would get from it. If I was living in Russia and some random person, be it on the street, at my door, or over the phone, would ask me my opinion on the war or Putin, you'd sure bet your ass I'd sugarcoat it in a pro Russian way, or at the very least try to avoid speaking to said person at the bare minimum.

And yes, people who said something against the regime on his channel got in trouble before. So Russia is very much aware of his channel and monitoring it, or at least have people watch it and report people they see there.