@djsumdog >But if you're writing a library in GPL (and it's not LGPL) don't expect anyone to use it.
Proprietary software developers being unable to use it is the whole point.

They either can join the free world and respect the users freedom, or they can't use the best libraries in the world is one of the tactics that GNU uses to defend freedom.

At least one piece of software that was proprietary is now free due to the choice of GNU Readline using the ordinary GPL (GPLv2+ I believe, although its GPLv3+ now) - the developer could have torn out line editing support, but determined it was easier to stop trampling the users freedom (too bad someone has now written a readline implementation that doesn't defend freedom, but thankfully that rarely happens); https://www.gnu.org/licenses/why-not-lgpl.html

GPLv3+ libraries are used heavily in free software - exactly where they're intended to be used, despite how hard those with proprietary agendas seethe.


Btw, there's a good chance that proprietary software company is infringing the LGPLv2 and LGPLv3 by a blanket freedom-denying clause that also demands that reverse engineering to find the malware is not allowed, while those 2 licenses require that reverse engineering for the purpose of debugging modifications is allowed.