Why does Minecraft keep spawn chunks loaded? [closed]

I don't know the full story, but apparently a long time ago (beta or even earlier), this was necessary for respawns to work properly. I don't know the specific reason, but knowing how buggy Minecraft was back then, you probably would have fallen through the world if it wasn't kept loaded.

It's probably no longer needed to keep the spawn chunks permanently loaded, but on one hand, it's not a high priority to remove that and test various different situations for whether that affects them, on the other hand it is also very commonly used by technical players and even many not so technical players to keep machines loaded at all times, like farms. Some contraptions even depend on being loaded at all times.

If you don't need the spawn chunks and want to free up most their RAM, you could use /setworldspawn to place the spawn chunks far away, empty them completely of blocks and entities and teleport all players that spawn there to where they should originally appear. You can use /spreadplayers (archive) instead of /tp if you want to mimic the random placement at world spawn.