Like many threads on this site. IT's G1 focused. So the question is phrased G1ish. But please don't consider this limited to G1 if it's different in other shows If you feel it was different number in different media. Go ahead a say so, i'd love to hear it. How many Cybertronians were there on Cybertron before the war? How many are on the planet when they leave for Earth? So how many Autobots left with Prime on the Ark? What percentage of the Autouts do you think that is? How many were left behind or on other planets? Same for the Decepticons; How many followed Prime? How many were left on cybertron or other worlds? When the series is done with how many Cybertronian are on Cybertron? Or Earth or Nebulon or planet beast or any other place?
In Spotlight Prowl, it is said that there are less than 10 000 of Autobots and Decepticons alive, and probably there are a few thousand neutrals.
Maybe in terms of how many characters have been named but not how many Transformers lived on Cybertron
A lot and there were I assume tons of colonies in they have shown up in different universes. I assume they researched space and groups decided to go and colonize and maybe exported energon back to Cybertron.
I know they're supposed to be fighting for millions of years but I don't like that there's only thousands of them left. Of course I don't like the fact that they live for millions of years. I liked that in AHM, Thundercracker claimed they were thousands of years old. Pity that IDW changed it back to millions of years.
Don't forget that the return of the NAILs after the resetting of Cybertron established that Prowl's estimates were waaaaaaayyyy off.