@WandaSiri - This is one of the problems with online forums. You get into an argument with someone and exchange lots of posts before you realise that you are violently agreeing with each other!
Regarding not being offensive to others, you still completely discount the offence given to GC people.
I don't, but I'm trying to look at it how I think the courts would. What follows is a gross oversimplification, but it will do for now.
If your employer insists you do something that you find offensive, they need a good justification for that. For example, when talking to someone face to face you generally don't use their pronouns. That just isn't part of normal conversation. Saying that you must somehow work their preferred pronouns into every conversation would clearly be unreasonable, so your employer can't do that. There probably aren't many situations where your employer can insist you use someone's preferred pronouns. I think it would only apply in situations where you are using pronouns and it is reasonable to think your colleague would find out which pronouns you used, and it wouldn't even always apply in that situation. However saying you must not use their non-preferred pronouns in situations where they would find it offensive is a different matter. That isn't about saying you must do something. It is saying you must not do something.
Imagine that A and B are work colleagues. If A is a flat earther. B wants to say that the earth is a globe but A finds that offensive, A will just have to put up with it (although their employer could reasonably tell both of them to avoid the subject). However, if B wants to tell A that they are obese and A finds that offensive, B will have to keep quiet in most situations even if they find it offensive that they aren't allowed to say that A is obese (and notwithstanding the fact that A weighs 30 stone!).
As a general rule (but remember this is a gross oversimplification and isn't always true), if A and B are in a work situation and B wants to say something about A that A finds offensive, A's desire not to be offended is likely to win.