Indeed. What if you did that? Think of how many masters your app could be subservient to.
If you think you can replicate one of their core products by yourself or with a small team good luck.
Say AI enough times and your might even have a VC throw money at you.
Of course realistically your not beating SF, but your free to try.
Years I ago I worked with Oracle ERP which under the hood was just as you describe a fusion of different products from different companies that they had acquired. It was a maze of scripts converting from one format to another and thence to another, etc.