What do we know about Pavel Durov and his motivations? Not much, apart from his photos on Instagram. And that's the whole problem with private and centralized platforms:
But everyone has their own comment…
The only conclusion I draw from this: communication tools that are massively used should not be private, their technology should be open, and their governance should not be in the hands of a small group of people whose true motivations we will never know.
Go open source and go decentralized!