[roger albert]

I'm with Mark on this.

The tire manufacture doesn't know if the tire is going on a 375 or a 575 lb bike (and in extreme cases, even wider ranges) so their blanket recommendation can't possibly be right. (except when they've spec'd an actual application chart, but even then, they often look like devoid-of-weight-context generalizations)

Otoh, the bike manufacturer doesn't know what the tire's construction is, except for that one particular tire, and even then only of the same generation, and thus can't be sure of pressure appropriate for your subsequent tire choice.

So, like Mark, I say fudge it in between and tweak to suit. And as Mal said, the rider weight and preference are further variables. Hard to objectively defend much different of an approach.