Jennifer Finney Boylan, a transgender writer and professor at Barnard College, appeared on multiple episodes of Jenner's TV show, "I Am Cait" and considers her a friend. But she's not an admirer of Jenner's politics.
"I wish her well personally," Boylan said via email. "But I can't see how the conservative policies she is likely to embrace will help Californians."
Wyatt Ronan of the Human Rights Campaign, a major national LGBTQ-rights organisation, said Jenner "is not the leader California needs."
"Her support of Donald Trump, the most virulent and vocal anti-LGBTQ president in American history, and her decision to hire Trump's inner circle for her campaign are just two examples why," he said.
David Badash, editor of an LGBTQ-oriented news and opinion site called The New Civil Rights Movement, noted that Jenner's campaign website outlined no policy positions and offered two options to those visiting the site: "Shop" and "Donate."
Badash questioned why Jenner would run as a Republican at a time when GOP legislators in more than 20 states have been pushing bills aimed at curtailing transgender youths' ability to play school sports and receive gender-affirming medical care.
Some activists found reason to welcome Jenner's announcement, saying it was further evidence that transgender Americans are running for office more frequently.
Rodrigo Heng-Lehtinen of the National Centre for Transgender Equality Action Fund noted that in the 2020 election, Sarah McBride of Maryland became the first openly trans person elected to a state Senate seat and Stephanie Byers of Kansas became the first openly trans Native American elected to a state legislature.
In Vermont, Christine Hallquist won the Democratic gubernatorial nomination in 2018, but lost the general election to incumbent Republican Phil Scott.
"Voters want leaders who will deliver results for their communities, no matter who they are," Heng-Lehtinen said.
Attorney Sasha Buchert, co-director of the Transgender Rights Project at the LGBTQ-rights group Lambda Legal, said when the public sees transgender people in public life it "serves to expand public awareness of the reality and diversity of trans lives."
"It matters to us what policies candidates support — and what their track record might be — on a full range of issues, not just trans rights and inclusion," Buchert added.
"That is the lens one should always use in evaluating any candidate, including Caitlyn Jenner."