It doesn’t matter if the content is encrypted in transit if Google can access the content in the app after decryption. That doesn’t violate E2EE, and they could easily exfiltrate the data though Google Play Services, which is a hard requirement.

I don’t trust them until the app is FOSS, doesn’t rely on Google Play Services, and is independently verified to not send data or metadata to their servers. Until then, I won’t use it.