I wrote a long post on here this morning, but lost it
Basically, the jist was that "biddable" is a pretty subjective term, and someone with less experience as a handler and trainer is going to have a different idea of a biddable dog than an average pet owner trying to teach house manners. People who participate in a ton of dog sports or working activities might be looking for the kind of biddability a malinois or border staffy has, whereas someone looking to get a CGC and teach fun tricks to a therapy dog that is primarily a family pet is going to have a really different idea.
Some of the breeds I've worked with where I've met a lot of very biddable individual dogs:
Aussies
Goldens
Springer Spaniels
Pomeranians
Poodles
Great Swiss Mountain dogs (but I've only known a few and they may have been from the same lines)
Pit Bulls - the more "watered down" lines that are common up here, not what are considered "hot" working line dogs.
Rotties
Boxers
I think it's a lot easier to look at what dogs aren't biddable.
Also, in which ways do you want the dog to be biddable? Do you want the dog to be looking at you for direction regarding house manners at home, and be easy to teach simple tricks and basic manners to? Do you want a working dog? A dog that is going to be very focused on you naturally in public places/with distractions?
I think the best direction I could point someone looking for "biddable" as an average or hobby sport dog owner is that lower drive, more pet/show bred herding dogs (aussies, GSDs, BCs, even OES), or sporting breeds that aren't as super-excited about strangers/stimuli (think springers, chessies, etc. VS labs or cocker spaniels) are going to be a good start.
I could also name breeds that are generally super biddable (like some people said, malinois, working bred GSD, IME rotties, lots of sport-bred BCs, even JRTs, etc) but are going to need a lot of training and management to make that biddability usable over their really high instinct intelligence, reactive tendencies, etc.