Unfortunately, it is not a growing market segment. [1] Sales are down 54% YoY in 2020 (and were well in decline before COVID). [2]
Samsung used to have their own line of discrete cameras, with quite a unique feature set for their time, but these were discontinued in 2015. [3]
15 million units a year is not a large enough market for any new entrant to bother investing the R&D. They would then have to license an existing lens mount or design their own, and photographers with thousands of dollars in lenses are very conservative about moving to a new system. Third party lens makers are also slow to redesign their products to support a new system.
[1] https://www.statista.com/chart/5782/digital-camera-shipments...
[2] https://petapixel.com/2020/11/06/camera-sales-in-2020-have-p...