Note: This answer is intensely opinion based and highlights what, to me, is the most important difference.
You can often avoid using pronouns altogether. It's actually pretty rare to need third-person pronouns at all on most Stack Exchange sites. But conspicuously avoiding using pronouns for one group of people while using them normally for others is a way of refusing to recognize their identity, and that is discriminatory. Please don’t do that.
If they are the pronouns stated by the individual, you must respect that and use them.
(bold emphasis mine)
The old version compelled us to use certain speech. The new one only requires us to treat everyone equally.
Compelled speech is evil.
A requirement to treat everyone the same is perfectly fine.