

Most often, yes. But there are exceptions. A lot of Ubuntu developers were on Debian in the early days for example. I imagine some still are - there’s a bit of overlap between Debian & Ubuntu developers here and there.
I maintained packages in various BSDs pkgsrc/ports tree, even though I never daily drove any of them, and had them in a virtual machine at best.

Hungarian: “A nap végén kérlek pakoljátok egymásra a székeket.” (Rough translation back to English: “At the end of the day, I ask you (informal) to stack the chairs on top of each other”).
Same thing, but more formal: “A nap végén kérjük pakolják egymásra a székeket.” (~English: “At the end of the day, we ask you (formatl) to stack the chairs on top of each other”).
In an even more formal / authoritative way: “A nap végén kéretik a székeket egymásra pakolni.” (back to English: “At the end of the day, chairs shall be stacked on top of each other”)