I discussed a Theory regarding Simmons in a previous Althouse post. I think it certainly sets the groundwork for his gender transition.
I hope this helps put Richard Simmons' seclusion in better context.
From that Theory:
"Richard Simmons shattered the glass ceiling that prevented Non-Celebrity Fat Women from having their own Magical Asexual Gay Guy."
Being a Gay Man that presented as Asexual and then was cast aside by better-looking non-threatening Celebrity Gay Men ('Queer Eye For the Straight Guy' as but one example), Simmons obviously suffered severe self-doubt leading to questions about his own worth and Identity.
Rejected as an Asexual Gay Man, Simmons really only had two options left to him: a SEXUAL Gay Man, or an Asexual Woman.
For Simmons, the second choice was a much easier path than the first.
As he was once a trend-setter in normalizing the Asexual Gay Man to Middle America he is now positioned to normalize Transgender Identity to those same people. They remember their previous fondness for Richard, and that helps them overlook any qualms they have of his new Identity: he was ALWAYS a bit 'off', but lovable.
Indeed, he is more effective normalizing Transgenderism to America than Caitlyn Jenner ever could: Caitlyn was once a Male Olympic Athlete, a Winner -- this places Him/Her outside a context that can readily be understood. But Simmons: he is still the Uncle who maybe hugs you too much but you love him, anyway.
I am Laslo.