That is insane. I can load all webpages on any laptop from 5 years ago. A browser doesn't become "slower". Even with bigger pages, they are still web pages, not 3D games.
It means the ipad itself is, for some reason, rendering itself slow. And you can't do anything about it because you can't hack it.
And your idea of the solution to the problem is to buy a new one ?
My god, somebody sell you a self-destructing product in order to force you to buy a new one, and you oblige ?