Experimental features are not enabled on a new world

Download level.dat file, add "enabled_features" tag as following tutorial shows - https://old.reddit.com/r/Minecraft/comments/11l5c4k/multi_server_with_120_additions/jbbxao3/

The strings have to match the current version features, find these from the disabled DataPacks (same level.dat file).

Also move the disabled datapacks to enabled (copy-paste). Remove old level.dat & level_old.dat, upload the edited level.dat, start up the server and check console with command "datapack list". New features should be enabled.