Dendrite is never going to ship, and if it does, it will never really have parity with Synapse. Mark my words.
But also, I am not sure that "parity with Synapse" is necessarily required or desirable. Sure, it needs to be fully functional and handle all the basic federatable communications, but its not like most small scale self-hosters need/want all the enterprise features being packed into Synapse. I think it is better for the Matrix ecosystem to have various server implementation that target different segments but can all still communicate.
I'd expect us to ship 1.0 once these numbers hit 100%, which at the current rate should be before end of the year.