No, there are not "many machines right now trying this" since all the compute power in the world could run for 100 trillion years and not find the private key associated with a public address. Would be a futile waste of time. That is why Bitcoin works; if the private keys could be found from a public one the whole protocol would be broken.

More generally, the compute cost to find that private key on average would far, hundreds of orders of magnitude, exceed the balance associated with that account.