Centralised platforms have strong economic incentives to invade privacy.

Its not really about FOSS vs proprietary. FOSS is better because it can be verified, but, for example, Whatsapp is better than a FOSS platform that is not E2EE and not decentralised.

Ideally we would use decentralised, E2EE encrypted FOSS.

Governments also like centralised platforms because they enable surveillance.