Open source licenses don’t prevent you from selling the product.
Also, you absolutely can open source the engine but not the assets. Maybe you are too young for this but idSoftware in the 90’s and 00’s always open sourced their engines after a couple of years, but the .wad data files remained closed and for sale. Also, you could have a closed source version, but create a fork which is open source (again, idSoftware did this with the Quake engine. They licensed Valve the closed source version, that’s why GoldSrc managed to remain closed source despite the open source release of Quake being GPL).
I wish more gamedevs today cared about hacker ethics.
Open source licenses don’t prevent you from selling the product.
Also, you absolutely can open source the engine but not the assets. Maybe you are too young for this but idSoftware in the 90’s and 00’s always open sourced their engines after a couple of years, but the .wad data files remained closed and for sale. Also, you could have a closed source version, but create a fork which is open source (again, idSoftware did this with the Quake engine. They licensed Valve the closed source version, that’s why GoldSrc managed to remain closed source despite the open source release of Quake being GPL).
I wish more gamedevs today cared about hacker ethics.
I know they don’t. But oopsie you missed my point to make an argument. What OPs looking for cannot exist. Pick 2, not 3.