No sandbox game can compete with gary's world which gets like 34,000 people daily. That's fine, no one is expecting blockland to get 34,000 a day.
But let's compare a smaller sandbox game to blockland.
I'd rather play with a 400 peak player base than 66 peak player base
Also this player base is not an accurate number for lego worlds because lego worlds is also on PS4, XBOX ONE and Nintendo Switch. While blockland is only on PC