As a Developer, I also don't look forward for integrating 50 frameworks for payment, deal with the limitations of each and every one and go through the bureaucracy of 180 countries for export compliance and taxes.
When you sell something through Apple, depending on the location of your user, Apple will act as Agent or as a Commissionaire. This makes everything easy, even for a solo developer. Sold an in-game coins in France? Apple collected the money, paid the VAT to the French government. If you do this through your own means, you will need to establish a relationship with the French government so that you can pay them the VAT that you have to collect from your users.
This will ultimately benefit large companies who can jump through the hops of managing all this, putting the independent developers in a disadvantaged position due to the high barrier of entry into improved margin(compared to Apple Store where everyone gets the same cut) payments. In some places you can be required to send a printed receipt to the user.
It would not be fun to watch, let's say Zynga, collecting their low cost payments across all their portfolio by making users sign up once and having indie games instantly losing a payment or falling back to high commission options because users are tired of entering payment info for each game.
Sad day for the little guy. Do you see independent Devs cheering for the %2-%3 commission or is it Epic, Netflix, Spotify who will benefit from this? Unless you do low margin commission work (like platform where you take a cut, i.e. online tutoring) the %30 commission is a non issue.
Game crystals don't really have a cost, so %5 cut or %30 cut doesn't really matter that much. However, one company having access to the %5 and other not having access to it will change the landscape because the large company will be able to advertise more thanks to its better margins, wiping out the rest.