The ignorance just goes on and on. Yes, GPL has been tested in court several times. The portions of a GPL project that are BSD or MIT licensed will remain so, but those licenses don’t require a derivative work to inherit the license the way GPL does. They specifically allow themselves to be consumed by another project so long as the licenses of those portions remain intact and attribution is given. GPL’s copy-left principle is different.
Anyway, just because you don’t understand how software licensing works doesn’t mean that others can’t and don’t. Read up about MIT, BSD, copy-left, and LGPL vs GPL. Google for a few minutes and find what the courts have determined to be a derivative work and what has not — it will likely surprise you. Doesn’t matter if it’s a separate library or dll: if you link it, use it, or it is an integral part of your program then your software is an integral work.