Microsoft already won this fight because of Gamepass with theirs. As they buy more studios and improve their first party exclusive lineup it will only get bigger.
Amazon, Apple, and Google do not have 23 first party studios producing a steady strem of AA and AAA quality exclusives for them. That 23 will only continue to grow.
Sony and Nintendo are the only ones that could compete on first party (and MS arguably had a more impressive first party lineup now), but neither have the infrastructure or funds to operate the infrastructure necessary to make streaming a reality for their customers.
I agree with what you say.
Maybe Sony and Nintendo will partner with the likes of Amazon and Google to leverage their infrastructure? That could ensure their 1st party games will rival Microsoft's.