That's definitely something we would like to make available at some later point for the content you generate within Fabric. Realistically though, because of just keeping something like the current thing between a team of 2 is a massive challenge, it would be later down the line.
Btw I know it's quite hard to make as an inherent feature for that kind of service, but it's still part of what I understand as the promise of "home for my memories".
If you have to do it the export way. Please make it an API, and put your data in open formats like odt, email, what ever open street map uses for map files, etc.
And don't forget. If you make a cool business that only runs for 2 years, you may make 6 or 7 digits of money. But if you provide a real solution for people's problems you make a living, even if the first business around it dies.
Thus if you make a home for all my memories it is not just important to connect all the data points, but to provide a solution that will exist for me, even if you as a company won't exist anymore. It must be a priority 1 topic for you to make me care about your product.
That being said, having a searchable, connected history of all my data points is really neat. Wish you all the luck in the world!