You’re allowed to draw whatever boundaries you want, but I can’t be the only one that thinks “installing accountability software” is a major privacy violation.
Going forward, you need to be very upfront at the beginning of a relationship that “no pornography” is a hard line for you, and be very clear what you define pornography as because even that definition is going to change person-to-person. For example, is it just videos of sexual acts? Is it pornography if it’s only one person in underwear? Is a thirst-trap heavy Instagram account pornography? Sports Illustrated Swimsuit Edition? Sears Catalog? Is it cheating if he fantasizes about anyone else?
Be prepared for this to be a deal-breaker for a lot of guys.