I'm not sure secularism has much to do with it, Frankfurt School arguments notwithstanding.

There have been plenty of authoritarian regimes throughout history (Qin Shi Huangdi comes to mind); the reason nobody was able to get all the way to totalitarianism in the past was because the technology wasn't there. The state simply couldn't control that much because there was no way to make it happen. Like it or not, you had to leave people with a good deal of autonomy.

So I guess inasmuch as secularism provided enough space for science to master the physical world sufficiently so that we could develop technology to actually functionally control almost every aspect of everyone's life, yes.

But otherwise, the impulse seems ancient, and only the inability to implement it appears to have kept things to be merely authoritarian.