I tend to agree, but this isn’t a unanimous opinion in Buddhism. I’ve heard he is all-knowing but doesn’t know all things simultaneously. I’ve heard he knows all that he needs to know if the situation calls for it. And some even say is all-knowing period.
"That is not so, because of its purifiedness. Because the Enlightened
One’s objective field is purified and it is unthinkable. Otherwise
there would be no unthinkableness in the knowledge of the Enlightened
One, the Blessed One, if it occured in the same way as ordinary
people. So, although it occurs with all dhammas as its object, it
nevertheless does so making those dhammas quite clearly defined, as
though it had a single dhamma as its object. This is what is
unthinkable here. 'There is as much knowledge as there is knowable,
there is as much knowable as there is knowledge; the knowledge is
limited by the knowable, the knowable is limited by the knowledge’
(Ps.ii 195). So he is Fully Enlightened because he has rightly and by
himself discovered all dhammas together and separately, simultaneously
and successively, according to his wish’(Pm.190-91).
VII,note 7. 9 the paramathamanjusa)
Even if it is someone different, it’s still in the Buddhist tradition. If one has the ability to come back from the dead and be eternal, wouldn’t that still contradict the Buddhist dharma of impermanence?