E.G. as they say about the CGI - computers became more powerful, but the minutes per frame have not generally changed year on year - they've just become more detailed.
A more accurate analogy would be building a 400mph maglev train line and discovering people are riding bicycles down the tracks.
Or that you've built a 400 lane highway but everyone's still stuck in traffic because they each made their cars one hundred times wider.
E.g. Instead of only using a car when you need to get there "now", you start using a car to get some coffee in the central area.
So there is no difference and that's why I mentioned it.
In general though, your analogy is much more true than not, since renderers are mostly optimized as much as possible.