Businesses aren't people, they're legal fiction. The individuals who make these decisions do and should have the right to do business with whomever they want, based on any criteria they deem appropriate. This constitutes the distinction between the private and public sphere.
There's a subtle distinction where you may have layered your own individual beliefs onto this statement by using the word "should", rather than indicating what is actually the law. While you may feel they "should" have that right based on your own feelings and personal morality, there are specific laws that say they do not. In many jurisdictions within the U.S., for example, businesses generally do not have the right to refuse business to a person based on that person being part of a protected class.
In any case, I disagree. Some things are basic necessities.
https://www.nerdwallet.com/article/banking/can-my-bank-close...
That said I do wish there was some regulation for accounts for Apple, Microsoft, Google, Steam, etc as closing an account can have huge reprocussions.