imo0 both are doing it.... they can't refuse Trump's candidacy because he has such a large following. popular elections are always dodgy as when it comes to such high profile demagogues.
as for Biden..... I've been watching the signs of cognitive decline for these 3 years. he's clearly mentally and physically infirm and needs to be politely and quietly removed. he's as dangerous as Trump, even though in different ways.
the "head-cold" explanation was justified. such illness has been shown repeatedly in research to worsen cognitive functioning in those susceptible to difficulties with mentation. his follow up speech from the auto-cue proved nothing but hi ability to read and perform in suitable conditions. its called masking.