Earlier quoted context omitted.
It is responsive as long as you use auto layout. Every other code generation plugin in Figma community is either paid or doesn't work anymore. I've tried Pygma and I just couldn't get it to work, it crashes when I'm trying to use it. Also, in contrast to Pygma, you don't need an account to generate code :)
I'm still getting absolute position output with auto-layout - it seems to be a mix of both. Yes the current public version of Pygma is no good - I've just been heads down trying to get the complete version working and haven't really been attending to the current plugin.
Yeah, that will happen if not every frame is in auto layout. Hats off to you if you manage to solve it for mixed modes with just flex layouts!