It is a joke, it's practically impossible to hack most of the games he said, and Blockland is too small to bother with.
Let me explain:
Blockland
TGE has good hack suppression, or nobody bothers to hack blockland. The exploitability depends on the add-ons used.
As for the Master Server hiccuping, it might be Badspot playing a joke from this post, server maintenance, or the same scenario as before: the shared server switch Blockland uses got DDoSed.
Roblox, Minecraft
The hackability of these games depends on the multiplayer server/place you are on due to the fact that there may be hack suppression add-ons. As for roblox, it is really easy to exploit. As for minecraft, it's sort of harder.
World of war craft, APB reloaded
Haven't played these but hopefully they have hack suppression like blockland.