This is really splitting legal hairs since WP is GPL and whether or not you make you’re plugin GPL or not…. While many, including myself respect the right of people to make money from their work, once someone has a copy of the plugin there’s really nothing preventing them from doing what they want with it. There are plenty people that will tell you that you’re plugin will be GPL because WP is, even if you say it’s not.
This argument rages all over the internet and I’m sure you can find plenty of opinions if you search.
That being neither here nor their…
I think the important part when it comes to ACF is that you’re not distributing the premium version of ACF for free, at least that’s my take on the statements on https://www.advancedcustomfields.com/resources/including-acf-in-a-plugin-theme/
