We are going around in circles. You are not matching the translations properly. And when you then write in English, what you say is simply not true. But let’s just get out of that circle and just ignore the words for a moment. They are just labels. We are talking about the process of an online sale. That’s what matters.
And that “document”, that IPS creates when a checkout is started need to exist when the order is submitted and—depending on the payment method—this means potentially BEFORE the payment is being made. That’s a fact. Please stop saying otherwise just because of your mistranslation of the English words being used. The customer needs a document to see what is being owed to the seller when they pay manually (e.g. via check or wire-transfer). The seller needs a document to demonstrate what the customer legally owes as payment. By asking for the “invoice” to be postponed until after the payment, you are asking for a legally required document to be removed from the process. And that’s why you are wrong when you say it like you do in English. It’s not a matter of opinion or country law. It’s just what invoice means in English.
Proof 1:
pay attention to “payment at later time”.
Proof 2:
pay attention to “sum due”, e.g. “still needs to be paid”.
You are clearly not using that definition and therefore everything you say in English is wrong and your feature request becomes unreasonable as well.
If those things don’t match your local translation, what needs to change would be your language strings. But please stop asking for the process to change (invoice after vs. before the payment), when it is legally required around the world.
The only thing that actually should change eventually is that the invoice gets postponed from the start of the checkout to the end of the checkout.