Permissive license means that whoever (say a corporation) modifies some code and release a software from it, they are not obligated to release the modified code under the same license. Which means they can use Open Source software to make proprietary software, make money off it, and the community receives nothing back for their labor.

GPL forbids this. With GPL anyone can still modifes the code and release a software from it. But it obligates that the modified code must be released as GPL too. So GPL guarantees that the community benefits.

The act of choosing a license political one. Are you willing to provide unpaid labor for corporations? Or do you want your code to benefit communities?