I come bearing sources.
https://web.archive.org/web/20120831045 ... laystation
This humiliating turnabout enraged Sony president Norio Ohga, but though it seemed sudden from the outside, problems had been boiling between the two companies for some time. The main issue was an agreement over how revenue would be collected – Sony had proposed to take care of money made from CD sales while Nintendo would collect from cartridge sales, and suggested that royalties would be figured out later.
https://www.eurogamer.net/articles/fare ... cle?page=2
For Nintendo's incredibly outspoken and honest boss, Hiroshi Yamauchi, neither of those things mattered. He believed - and he was probably correct - that the deal that had been signed with Sony was completely catastrophic for Nintendo. Under the terms of the contract, Sony - which had created the technology for the CD-based games - would actually control the SNES-CD format. It alone would have its hands on the reins of this format, essentially removing Nintendo's control over releases on one of its own consoles.
https://www.engadget.com/2015-11-06-nin ... works.html
Back in 1988, Sony inked a deal with the legendary gaming giant to add its then new CD-ROM technology to the upcoming SNES console. But when it came to money, they couldn't reach an agreement: Sony allegedly wanted to keep all the money from CD licenses and then figure out royalties with Nintendo later. As you'd imagine, Nintendo didn't take to this arrangement too kindly.