VISA most likely cares above all else about making money for VISA. Likewise, Steam probably doesn't care how people pay for their games : they just want to be paid. If they move away from bitcoin, it's probably because they deem it unviable / unprofitable / too much of a pain in the ass.
Not everything is a grand ideological battle, and there's no need to go looking for complicated explanations when the simple and naive interpretation makes eminent sense.
It's part of the general problem that bitcoin isn't really fungable for goods. Maybe it was back when the value was more stable or grew slowly, or the transaction fees were cheaper. But you're totally right. Currently it's barely worth the effort compared to traditional payment system in many contexts.
Not everything is a grand ideological battle, and there's no need to go looking for complicated explanations when the simple and naive interpretation makes eminent sense.