I think we should distinguish between social democracy in the imperial core and in the Global South. The first will inevitably capitulate to reactionaries, while the second is objectively pushed into revolutionary actions (even if they are completely unprepared for them and usually fail).
Currently existing society is already unable to reproduce itself in pretty much every aspect of its functioning: demography, education, infrastructure etc.
If people were strictly to adhere to the parts supposedly actually attributed to just Jesus, the Roman Empire would have never adopted Christianity as its official religion.
Because you can only vote for servants of the bourgeoisie.