He didn't have preseason with Chelsea, EtH had preseason with our team. Potter's first few results were a draw and a win or something like that, ten Hag started losing 2-1 to Brighton at home and then 4-0 away to Brentford. Us losing 4-0 in 2nd match of new season looked like same old stuff from last season (Watford, Brighton, City, Liverpool etc).
But main thing to me: if EtH is real deal, he'll most probably make it at United. If Potter isn't, he won't make it at Chelsea. Worrying about others' narratives shouldn't faze us much. Who cares.