"Most likely true, in a mass blitzkrieg type assault they are willing to absorb these losses(based on past ChiCom response)"
Lose 10% per sortie due to accidents, plus combat losses, plus coping with the inevitable counter-air campaign that attacks your airfields and aviation infrastructure, and you will very quickly lose your air force.
"If the ChiComs don't nuke any US territory or US mainland, will the the US be able politically to respond nuclear in the Taiwan theater?"
Yes. Once the nukes come out, everyone will decide that the ChiComs are stone-f***ing-crazy, and they'll treat China as a mad dog. You handle a mad dog by killing it.