This is incorrect. WhatsApp encryption keys are managed on server and hence can be MITMed on state warrants quite easily by WhatsApp unless you are very careful

This is incorrect. WhatsApp encryption keys are managed on server and hence can be MITMed on state warrants quite easily by WhatsApp unless you are very careful to follow key changes and verify keys physically - and even then how would you know since it's WhatsApp app that is showing the key, and not something you generated independently out of band with a different program. What the encryption does is prevent non state level actors from breaking into your conversations.