SAP has done a lot of bad things[3] but they pretty much standardized how business is done in most industries, whether you're a plastics injection molder in China, dealing oil out of Dubai, or the trader in Zurich making his fortune figuring out how to get that crude from Dubai and refined into some plastic polymer pellets to that Chinese plastics vendor (who'll sell those 50 cent widgets to you in a few months).
[1] We have the same thing in our industry, we just call it "vendor lock in". I sort of touched on how the "meta money" worse in fed contracts here (https://news.ycombinator.com/item?id=10807858). A CPA is basically a programmer maintaining legacy code (300 years of obscure tax code (they even call it the same thing)) feeding your input data (your quarter and/or years aggregate financial data) to produce output data (your 1040 or whatever). Edit: Havoc basically captured the whole "legacy" reasoning (a mentality of "they'll remember my potential failed project a lot more than they'll remember my potential re-implementation that will only slowly (but very substantially) accrue profits" is always in the back of your mind. There's a lot of politics when you reach the decision-making level and risk aversion is a necessary skill to adopt to keep yourself out of hot water.
[2] https://en.wikipedia.org/wiki/X12_Document_List#Financial_Se... or variants there of. Even other ERP's FI & Controlling (or AP/AR) will have some sort of 'Connector" that will enable you to talk to SAP in some fashion. You'll just be paying Epicor, Netsuite, or Oracle a few hundred k for the modules.
[3] Can't knock on it too much since I've profited directly from the convolution of SAP ECC 6, but I certainly I generated more value for the clients than I billed.
Some folks (like Quicken in the US) use automated download as a way to insure upgrades (they periodically make it impossible for previous versions to work any more so that you have to upgrade or lose the capability). I got sick of that and wrote a csv ingester in perl.
But business has been transacted, literally, for thousands of years and there is so much variety there. I don't expect full automation until we have even better cognitive tools which can dynamically adapt to what ever is needed.
So that leaves you with a patch work of things and not a lot of incentive to unify them. It reminds me of the CAD framework initiative where engineers tried to unify the sharing of CAD data, except the CAD vendors figured out that lead to less "stickyness"[1] and started working against it. Banks are no different, there is nothing to distinguish bank "A" from bank "B" with respect to holding on to your money.
Payments and invoices are a bit different, working with the vendor, if you are a B2B business you can often negotiate something if you are B2C you are in a stronger position to simply insist that your customers use your automation tools.
[1] This term has been used to describe tools and techniques that make it hard to switch from one provider to another, thus maximizing your "customer lifetime value" often at the detriment of the customer.