I've seen a video that Softbank's CEO Masayoshi Son is one of the friends of the NVIDIA Ceo Jensen Huang. He invested on NVIDIA early, he made a profit although it's not the maximum amount but it's still a lot of money. So, a quick summary - Softbank is an investor in various sector and in technology. So, if this venture gets to happen and they sees Bitcoin as a good asset to invest since it's got blockchain technology, they'll invest heavily on it.
Masayoshi Son actually is so popular that I thought everyone already know him.
But indeed softbank is a big player in the investment world, any cutting edge tech that we've seen so far, there's big chance that softbank has invested in it.
Although frankly speaking softbank also caught in a massive flop sometime, i'm talking about we work and so on.
Just like with anyone in the big investors world, nobody is all white or all black - they are somewhere in between.