Here are the two sides to your argument.

Probability builds over repeated attempts. vs. Exponential decay towards certainty.
Because keys are deterministic 0-1,000,000 are the same.
Ranges reduce time complexity.
It only appears that each key is independent over a distributed field but they are repeatable.
Every key maps to a public key and is used to sign messages or transactions and only that key will move these bitcoins.
By the way when did it become 'OK" to post private keys online>FUD