No, you didn’t. You said that self-hosting nextcloud is a pain in the ass.

The metadata-issue is addressed in their FAQ

And to the blocking issue:

There are significant benefits to using email as transport in a hostile network environment. As mentioned above, it is infeasible to block email protocols across a network, because everyone relies on email for everything. Since there’s no way to differentiate Delta Chat messages from emails on a network, Delta Chat protocols can’t be blocked without blocking all email. Individual Delta Chat servers can be blocked, but the protocol cannot be blocked network-wide.

From signal-contingency-plan.info

Deltachat is really good, decentralized and basically unblockable (unless the government blocks the email protocol… which would break the internet)