While I agree that in many (all?) ways it is that simple, this is an area where there is a lot of scope for there to be unseen pressure from intelligence agencies. The French literally invented espionage (I choose my words carefully here) let alone whatever pressure comes at Telegram from elsewhere. It is hard to be confident in the whys of decision making around large communications tools and security.

Although, ironically, if the French are arresting him now that says good things about Telegram and their willingness to dob customers in.