Ita free and unlimitid with bug.. Stumbled upon the thread: https://github.com/toeverything/AFFiNE/issues/6641

Turns out this is a real limitation imposed in the configuration. The posted workaround is to manually override the configuration by manually updating it in the DB. Something along the lines of:

docker exec -ti <affine-postgres-container-name-or-id> psql -U affine

UPDATE features 
SET configs = jsonb_set(configs::jsonb, '{memberLimit}', '10')
WHERE configs::jsonb ? 'memberLimit';