If you want to distribute mobile apps and reach all users - something that is required for any kind or collaborative app - you MUST support iPhone in the western world. In fact, it’s often iPhone first, Android second.

And on the iPhone, you MUST use the Apple App Store, not just as a means to distribute your app, but as your payment provider. You can’t collect payment details yourself, use Stripe, Paddle, anything. You MUST use Apple.

You simply cannot enter business without paying Apple a share. That’s a monopoly.