It really depends on what you consider hacking. Aimbots are still possible, are those considered hacks? You can exploit some excessively common mods I won't mention to do things like what you said above, which is probably what they were doing. Blockland in it's vanilla form is pretty airtight-- nothing can be done to the server as far as I have heard. Client mods still can be used as 'exploits' though. I have a working radar + aimbot, took some changing in the code but it works and that's all that matters.
Aside from that, as far as actual hacking goes, Blockland is completely hackable. DLL injection can be done to any program, and I know people that have been working on it for a bit now and their only real trouble is they can't find an efficient way to locate the console object's memory address so they can inject C++ console functions. It'll be amazing once they finish, though. C++ add-ons will run incredibly fast and can do things normal add-ons can't.
