I've been wondering about this for quite some time and finally found my way to this thread. If you're new here like me, HOME SCREEN rotation is simply not supported on the Xs Max at this time. I bothered to read the thread before I posted. The details as to why are all in there but that's the bottom line.
What's even more astounding than the fact that it's not supported, is the sheer number of people that just posted answers with absolutely no clue as to what the REAL question was. Un-freakin-believable. And we wonder why society is doomed. Some people are so dying to speak that they never bother to listen first. Witness no more than this very thread as evidence.
(This response was not intended to be directed specifically at Darkmom05. I did not see the general reply at the top before I made this post originally as I am not intimately familiar with the forum's support formats and software. Please forgive that oversight.)