Is there a way to change a "My Page" so that it can be used throughout the organization?
Unfortunately you can't. "My pages" is an additional personal functionality for end users to somehow change the main (master page) for their needs without affecting itself.
Changing the master page (which can be available for anyone in organisation) is based on Page Builder role. That one is available for users who passed Anaplan UX training within their organisation and requested this via tanant admin.
You can share results of your custom personal page using export. You can export either full page as PDF. Or export particular table on the page in various spreadsheet formats.
Also want to add that if you have any nice idea to add to the existing functionality in Anaplan I'd recommend you to search it in Idea Exchange and give it a Kudo or if it's not found to raise one to get it into community's attention and possibly see it in the future Anaplan releases!
It is possible to convert a personal page to an app page if you have Page Builder permissions on your tenant. You can ask your tenant administrator for this level of permission.
If you were looking to share a My Page with others without it becoming a full app page, it's not possible today. However, there is an open idea on the Idea Exchange on this topic: https://community.anaplan.com/t5/Idea-Exchange/New-UX-Share-My-pages-with-other-users/idi-p/74957. Feel free to give it a kudo and subscribe to it!
Thanks. Just gave it a thumbs up