Are those things true, or as significant as they sound? (Not being able to directly port my source to another service sounds quite risky...)
That’s ancient history, particularly with these recent launches, as Google Cloud has become a real platform.
This is vanilla node. You need not use Datastore, and can happily talk to a managed MySQL or Postgres instance via Cloud SQL (albeit sadly still via public IP and/or a proxy for now). The same is true of the recent Java 8 support, and will be true of all the new runtimes going forward (as mentioned downthread, the Google I/O talk is the best reference here).
Google Cloud Functions is similar, fwiw. You can even package up arbitrary binaries and exec them (ffmpeg is a favorite, as is imagemagick’s convert).
I'd way rather program in JS than Python [edited: thanks yathern], especially now that async/await is a thing in Javascript. Very cool work by the Appengine team.
Node is JS, of course (with a different standard library). Did you perhaps mean to compare Node to python or something?
By contrast, I deployed an app on Digital Ocean and, though they have a solid product, I eventually shut the instance down to avoid paying the monthly fee on an app I rarely used.
https://www.youtube.com/watch?v=ogexnfng_hE&t=515s
The new runtime is 100% idiomatic without any special apis. We do offer certain native libraries pre compiled system libraries (to support headless chrome among other things) and certain ENV Variables for gcp API tokens.
You should be able to lift and shift a GAE Standard Node.js app to any other provider with minimal overhead.
I can't make direct promises regarding the runtime update cadence, but I can promise that I work closely with the people responsible for this and they care a lot about getting updates out in a timely fashion. The new runtime stack makes this easier to do than previous GAE Standard runtimes.
(Disclaimer: I work for GCP)
And you should stop telling others what works best for them without knowing anything about what their projects and needs are.