While Sony might restructure eventually, it would be enormously expensive and legally complex, so I think Kadokawa would continue to exist as-is for a good while.
Also, this article ( https://www.pushsquare.com/features/why-would-sony-want-to-buy-kadokawa ) seems to imply that this might be less about Sony being aggressive and more about Kadokawa being in a vulnerable state. If it really is a situation where Kadokawa might end up in the hands of foreign investors then I think the Japanese government would be behind Sony.
Also also, GAMERA CINEMATIC UNIVERSE!!