1. We've released a codemod when releasing v3 and allowed users to upgrade easily from v2 to v3 and we're planning to do the same for v4 as well. https://refine.dev/docs/migration-guide/
You should just answer the question instead of pointing users to GitHub. The answer is no, they are not and they plan on selling features in the future.
Thank you for your warning and comment. I shared the link because I thought people could contribute to the discussion on GitHub. To avoid any misunderstandings, I want to clarify that Refine will always remain open source and will continue to be developed with the community. So we are adopting the "open core" model which is very popular and widely accepted in the open source ecosystem.
To reiterate, Refine will always remain open-source.