I don’t know a lawyer, but if I understand it correctly, a permissive license means 1) companies like Google can bolt proprietary code onto your product and use it to make millions competing against you without any obligation to share or give back, and 2) you can lose out to a restrictively licensed fork the way Apache-licensed OpenOffice lost against LGPL-licensed LibreOffice, because LO could incorporate new OO features and improvements, but OO couldn’t incorporate new LO code.