I’m an atheist, and a staunch believer in secular government. I have absolutely no love for enshrining Islam (or Christianity, or Judaism, or Buddhism …) in law or government.
That being said, it’s important to be fair here: It is entirely possible to give Shariah law a role in a government without creating a regime akin to the Taliban. Malaysia, for example, affords Islamic law a special role in its courts. Now, you might argue that Malaysia doesn’t do the best job of protecting the civil rights of its citizens, and I’d agree with you. But I believe Freedom House describes Malaysia as a “partly free” country, and that’s about right - there’s a vigorous press, independent courts, women can participate in public life, and so on. The Malaysian government isn’t the Taliban; even if religion is enshrined in the Libyan state, there’s no need for the new government there to be the Taliban, either.