You conveniently forgot about the second part of that comment. Durov was forced out of the country and had to cell vk.com for peanuts because of his refusal to cooperate with the government. He is still pissed off at the country at large (not just the government) and refused to add the Russian translation for years, for example, despite it having absolutely nothing to do with Putin.
Since he is Russian in origin, it's okay to throw baseless accusations at him and spout nonsense like "maybe they're FSB agents" or "maybe they hired an FSB agent without knowing it". You see it here everywhere, and HN is one of the better sites in that regard. Well, maybe Signal has hired an NSA agent and doesn't know about it either? How does that sound?