Fully agree. The law of diminishing returns sets in pretty fast and then it is an ugly race to the bottom.But even more important, letting random sites run cpu heavy js is more uncomfortable than seeing an ad or two. I just wouldn't visit such a site (without noScript anyway).
Web is diverging to two poles for a long time; free-for-all-ad-and-malware-infested-stuff and gated-gardens (money or other-wise). What can't be monetized (or supported by other means, like business sites) and doesn't have a strong community will die. And that's ok.
Participate or consume, the choice is upon you.
- cx -