That's literally what faster IO does, last time I checked. You've been given a theoretical lesson that anyone who knows anything about how storage interacts with memory already knows.
Mind you, this is 100% theoretical and a giant oversimplification because there are big diminishing returns you get with "better textures" above a certain resolution, and modern compression methods make these returns even narrower on top of higher costs of making higher resolution textures.
When you ask some indie dev who is making a game that doesn't push the hardware at all about the limits of hardware instead of asking them about their game, a theoretical oversimplification with absolutely zero value is all you'll get.