Can I have a custom hosted manage preference page that allows subscribers to opt in and out of lists, not just segments?

Hi, I have a client who has asked me to build a custom hosted manage preference page for them., which I have done. The problem I’m running into is making sure everything is working properly as my client has created lists for each interest choice, as opposed to segments. For example, the options they would like to enable their subscribers to opt in to are shown in the image below. Each option is set up as a list. As I understand it, the best practice with Klaviyo is to have one master list, and then segments to manage preferences, but my client prefers to keep things as they are, by using lists.

Based on ‘How to custom code consent pages’ it looks like it should be possible as it states:

• Information that can be used to target and segment:
  • A checkbox for whether or not the user wants sale announcements
  • A checkbox for whether or not the user wants product announcements
  • A checkbox for whether or not the user wants blog updates
  • Other lists the user may want to join

However, everything else I read says it’s not possible. Are subscribers able to opt in and out of lists from a custom manage preference page?

Thank you! Claire