(1) serializability will not be "fast anyway". it will be slow. this is the problem with, for example, mongodb's global write lock.

(2) you would not get "lots" of aborts with bank accounts because each transaction is, typically, to a different account. you're only going to get a problem when two processes try to change the same person's account at the same time.

(3) what this provides is standard-compliant ACID sql, the same as postgres, oracle, sql server, etc. if you use any of those and don't have retry in your code for when transactions fail then you're already in a mess.

i am not associated with this project, but what you're saying doesn't really make sense. as far as i can see, you're criticising it for being the same as everyone else in the standards compliant, sql world.