AMP gives WSJ an incentive to serve a faster version. Why would they spend money improving their site - especially a big name like WSJ? Plus, from what I've heard from developers working at new sites, "our pages are faster and use less data" is a hard sell to the people in charge, who are more interested in integrating yet another ad platform.
Exactly this. the AMP badge is a visual indicator that says "we're not going to waste time your time with a slow loading webpage, so click this link over one that doesn't have the AMP badge", which incentivizes faster webpages in a way that wasn't available previously.
most clicks go to sites that are on the top of the search results, therefore prioritizing placement due to pageloading speed should be enough of an incentive to most sites. The AMP badge pretends to be an incentive in this way, but the purpose is to extend google lock in.
What would that be, out of curiosity? Not asking rhetorically. I would just assume the exact opposite -- they have every incentive to provide a monetized, just passable enough to be consumable experience. The content (and ostensibly the design) is the product, not the load time. Performance seems low on the list.
