There are FOSS games with a single branch for development, which doesn’t scale well for stability, but works fine with slow development.
Others, have stable and experimental branches with backporting and so on. Probably works better, but too much delay between stable and experimental makes people play on experimental. Stable releases are expensive (redundant bugfixing, backporting, feature freezing/completing etc.), so not every projects has or wants them. Fast development might enable modding to turn into internal (optional) features though.
Modding relies on stability AFAIK.
There are FOSS games with a single branch for development, which doesn’t scale well for stability, but works fine with slow development.
Others, have stable and experimental branches with backporting and so on. Probably works better, but too much delay between stable and experimental makes people play on experimental. Stable releases are expensive (redundant bugfixing, backporting, feature freezing/completing etc.), so not every projects has or wants them. Fast development might enable modding to turn into internal (optional) features though.