Not mutually exclusive, but they compete for resources.

Prefetch/prerender use server resources, which costs money. Moderate eagerness isn’t bad, but also has a small window of effect (e.g. very slow pages will still be almost as slow, unless all your users languidly hover their mouse over each link for a while).

Creating efficient pages takes time from a competent developer, which costs money upfront, but saves server resources over time.

I don’t have anything against prefetch/render, but it’s a small thing compared to efficient pages (at which point you usually don’t need it).

> Creating efficient pages takes time from a competent developer, which costs money upfront, but saves server resources over time.

Not trying to be a contrarian just for the sake of it, but I don't think this has to be true. Choice of technology or framework also influences how easy it is to create an efficient page, and that's a free choice one can make*

* Unless you are being forced to make framework/language/tech decisions by someone else, in which case carry on with this claim. But please don't suggest it's a universal claim