I was curious if "NOT WELCOME" meant "not legally allowed", so I went to the license page. Turns out it's a modified Apache license that prohibits certain entities from using the software, but not supporters of certain political parties; instead, it prohibits the use by governments of various nations:
https://sql-workbench.eu/manual/license.html#license-restric...
Note that this means the software isn't open source, and can't be linked with GPL code.