Let's not conflate the text/HTML-based syntax and the distribution channel implemented by Google. You can render an AMP document with your own implementation of the AMP custom elements. Can I do anything remotely similar with Instant Articles?

The problem is that for amp pages to work with Google search, which everyone uses, it needs to use Google's flavor.

Google should just stop pretending that AMP is any different than fb instant articles. Yeah it gives you more syntactical freedom and you can run some scripts in iframes, the lock in factor is the same.

Not sure why it matters that the scripts are hosted by Google, you can easily add hashes to external scripts to guarantee they haven't been altered.

Yes it's more open than fb instant articles but both act to build a fence around open web

That's all totally fair. But in my original comment, I tried to center my observation on how Facebook has threatened the openness of the web with a proprietary alternative. Is it even possible for Google to deliver the same features without drawing a line around something? If so, how does that hypothetical thing differ from AMP?

Probably not. It's just the marketing that gets me. Google should say "use AMP, a Google alternative to fb instant articles!" Not "use amp it will make your site faster!" Which isn't true.

Worse is that users will start associating the amp icon with fast sites, forcing everyone to start using amp or suffer lower conversions even if their normal site is just as fast or faster. This is because google forces amp sites to be fast, but doesn't punish slow sites in their other search results. Suddenly this amp thing starts to look less innocent.

There is absolutely nothing stopping google from putting an icon next to fast sites that don't use amp. They used slow sites as an artificial crisis to market a fence they're building around the open web.

Pretty dark for the "don't be evil" google. Facebook isn't doing anything better but at least their platform doesn't pollute search engine results