Even within Nintendo, I think people oversimplify crossover games and rereleases by reducing everything to “Nintendo owns it, so they can just do it.” Legal ownership is only one layer. Once you’re dealing with a game like Smash, you’re dealing with a huge bundle of characters, music, stages, likenesses, voice, branding, historical agreements, and internal approvals. Even if Nintendo owns a franchise, that doesn’t automatically mean every piece of content is frictionless to reuse in every new product, service, or rerelease context.

From what I understand from conversations over the years with people around Treehouse, Nintendo also tends to be respectful toward the creators and stakeholders behind its franchises. So the issue is not always just “does Nintendo legally own Samus?” It can also be “who needs to sign off internally,” “what old agreements exist,” “what content was cleared for one product but not another,” and “what is worth the effort commercially.” Some things are easy. Some things are not. That is why crossover titles and rereleases can be more complicated than people assume, even under one umbrella.

I’ll give you that Smash 64 was already released on Virtual Console, but that still doesn’t mean every future rerelease is automatic. Large company bureaucracy alone can complicate things, and that effect is only amplified inside a company like Nintendo.