The fun thing is...why oh why depend on other castles like aws? Servers are cheap, independent Data-centers are here, and good system administrators (like myself..of course) are still a living species (although on the brink of extinction outside habitats like finance and insurance etc)
OTOH, their volumes did not justify the complex environment they allegedly had and they should be very well within the skill set of the very average devops engineer. No large scale deployment expertise required.
Parler got popular amongst Trump supporters and nothing draws negative press like Trump.