It's interesting that the article was saying that they didn't really design them for video or content creators, but that's how people are using them. Maybe an M50 mk III will get 4k video with no crop and with DPAF?
I haven't seen a end-of-production date before. Manufacturers will make batches of each product as needed unless the volume is large enough to have a continuous manufacturing process. That date normally isn't available outside of the company though as it isn't customer facing. You never know how much product is in finished good inventory or on distributor/retailer shelves.
Different geographies have some autonomy on products they carry, e.g., the M2 wasn’t released in North America. Perhaps Japan and Australia felt the M6II wouldn’t sell well alongside the R10, so they stopped selling the M6II in advance of the R10’s launch. Canon management in other countries felt differently, so the M6II remains ‘current’ in most of the world.