It should be up to the employer. If one company thinks that a past conviction is irrelevant while other companies think a past conviction is disqualifying, then the former may get the employee at a better rate, the company will thrive depending on whether they were right, they'll have more resources to hire ex-cons, and other companies will follow suit.

A blanket law that forces all companies to hire employees without considering information they think is important is really inefficient. Just recently, governments and people were complaining that rideshare companies weren't being exclusive enough! If you think new laws will find the optimal policy for all companies, you are incorrect!

It's also overreaching. Freedom of association is important. The owner of a Jewish deli shouldn't be compelled to hire a formerly convicted neo-Nazi.