While I'm still firmly in the camp of Kang not showing up in this show and especially of Kang not being the real villain of the show, I do think it has more plausibility than the ridiculous Mephisto theories form WandaVision.‘Loki’ Has Made Kang The New Mephisto, But The Theory Has Weight
Even Forbes getting behind the Kang theory
Might have to go full throttle with this theory
I personally think Ravonna is more than capable of being the main villain of the show and they could even have her allude to Kang as being one of the reasons she's trying to wipe out divergent timelines (there are nuggets in her comic book history that would explain why she'd be focused on this task) but unless it is a last minute decision to re-write the final episode script and have Jonathan Majors film a quick cameo in front of a green screen, I don't see Kang being a main focus of this show at all.