I work for a company run by evangelical Christians, and this extends to probably 80% of the company. Certainly the only people taking about religion are the evangelicals. Management attends explicitly Christian "leadership retreats". Among other things, I would not be comfortable attending these events. Officially discussion of religion and and politics is discouraged. In practice that means the conservative culture warriors are vocal about whatever issue they're worked up about.

For the trans people I know, "acknowledge the existence of" them basically means to treat them according to their self-understanding as communicated to you. Usually that means using the name and pronouns that they identify with and not asking invasive questions. The idea is, roughly, that you are acknowledging that they - the person in front of you, a real physical body presented according to their self-understanding - exist. Dead naming or using a gender assigned at birth would imply that you are making their identity subject to your own model of the world, they're an abstract notion to you. Or, worse, that you are addressing a person that doesn't, in their conception, exist. It's imprecise language, perhaps, and not every person experiences it the same way.