This is misinformation. Yamaha will be in the business they have always been in, an engine builder. They just happened to build snowmobiles, and when they stopped doing that, they supplied engines to AC/textron, while still sticking with their core business as an engine builder.
Nobody said they will be stopping their engine supplier contract, they stated that they were going to be out of the sled building industry. Even if AC drops the 7000/9000 sleds or starts building their own, Yamaha still supplies AC/Textron with 998NA engines for their Wildcat XX.
Who knows, those both may change for MY26. But you can bet one thing that will not change, is Yamaha allowing anyone to assemble their engines. If you ever see that happen, I will start burning all my yamaha clothing.