Elon is not "untrustworthy" because of some ambitious deadlines or some stupid statements. He's plucking rockets out of the air and doing it super cheap whereas all competitors are lining their pockets with taxpayer money.
You add in everything else (free speech, speaking his mind at great personal risk, tesla), he reads as basically trustworthy to me.
When he says he's going to do something and he explains why, I basically believe him, knowing deadlines are ambitious.