Regarding white supremacists, I think you are overlooking how this debate empowers extremist groups whose actions are akin to the discrimination, persecution, and other atrocities historically inflicted by institutions like the church on the LGBTQ+ community. I believe the legal frameworks that already exist to fight discrimination should be applied to protect trans people from similar behaviours. Respecting their right to identity should not be relativized, just as it is not relativized for anyone else.
Something that needs to be pointed out.
1) Any law restricting what a white supremacist can or cannot say, is a law that, at a minimum, creates the precedent for a restriction on what good people can or cannot say. The problem isn't coming from empowering them, the problem is coming from what happens next. You always assume that good people will make the laws, but I am always concerned about what happens when laws are twisted by bad people.
2) We have laws protecting trans people, I am in favor of THOSE laws. I am not in favor of laws FORCING me (even though I give no push back to the polite attitude towards trans people) to use certain language when describing them. I will gladly do the right thing, but I don't think it should be a LEGAL requirement.
3) I think this is a good point in this conversation to make a statement. I am DJ 0045. Let's be clear about something here, I am probably the ONLY person on this site who is not anonymous. It would take about 10 minutes of effort to dox me. You all misname me, and have been doing so for years. DJ is NOT my name, the distinguishing name for me is 0045 (or if you really insist on shortening it, you could use "00"). Imagine, even here in this meaningless environment, if I were to start insisting that you all call be by my real nom-de-plume. Imagine if further to that I started reporting everyone who made a mistake and kept calling me DJ. Imagine if even more ridiculously, GoboStatus agreed with me. I would never do any of that, but let's be clear about what we're talking about. Furthermore, by this point, you should all know that DJ 0045 is my full nom-de-plume, and that DJ is clearly not an appropriate shortening of DJ 0045, because there are literally thousands of DJs, but only one 0045.
4) now imagine, if I were to suddenly, out of the blue, decide that you are all being disrespectful by calling me DJ, despite years of that being the norm. How quickly would you be able to wrap your head around the change? And let's be clear, this is obviously a meaningless example, but it would already be very difficult for most of you to have that change seem natural. It would be exceptionally weird if I started insisting that you all think of me as 0045. etc... etc... etc... BUT the real problem would only arise, in the event, as described earlier, that the authorities on this site, chose to ENFORCE that change.