From a political point of view, irreligion is religion. Telling every single person who works at a location how they are or aren't allowed to peacably express their religious views or lack thereof is a religious action by government. By definition, not secularism.

It's ok (-ish) to actively seek an atheist state, but it's duplicitous to do it under the guise of secularism. The separation of Church and government (secularism) most accurately means that government "make no law respecting an establishment of religion or prohibiting its free exercise". I hate to go all "Murica", but the concept is secularism is often tied to that prior quote. How is telling people they can't wear a cross or pentacle or anything in between anything but "prohibiting its free exercise"?