What is the problem with submodules? I like to use them because it means the code I need from another repo remains the same until I update it. No unexpected breaking changes.

Using a package manager to share code between repos has worked far better for me than submodules.

This comment sums up the issues better than I could: https://news.ycombinator.com/item?id=31792396

”Ready for liftoff?” should have a go-pro button. That’s all that is needed.

Why have a call-to-action to something they don't want you to do?

It's only there for Pro users and people who want to support the project [1] and not normal use.

[1] https://data-star.dev/essays/greedy_developer

That you have to go looking, actively, to realise there is a paid option.

Can i share my history and bonus with my desktop, ie linux?

Oh, it's closed source ios/macos only? Yeah, no thanks.

I also kinda doubt it's compatible with most firefox addons, addons can and do rely on details of firefox that ios does not provide the ability to emulate.