That's fair but Espressif is wayyyyyyy more open than ANY Western chip maker. The entire framework and toolchains are open-source for one thing. You get listings and sometimes pseudo-code for the internal ROMs (though no code). You get full access to datasheets, technical reference, and sdk documentation. Everything in their SDK is documented. You even get help on github. All of that accessible to anyone anywhere at any time.

Contrast that to the last time I worked with Nordic in a professional manner, I had to sign NDAs to get the full documentation and toolchain. Their toolchain contained binary blobs that when inquired about you get told "don't worry about it ;)" which is shockingly frustrating when a crash occurs in them and you're left trying to work around it. And if you're not a professional you're basically SOL and left with half-baked community toolchains, when they exist for a particular chip.