Those stock type builds just “are what they are”.
A bit more cam and some bowl work can really make a noticeable difference on a build like that.
But not every combo is built to be a hero on the dyno.
I wonder exactly what he used for a cam?
None of the factory replacements I know of are “.444” lift.
The std cam is .434, and the HP cam is usually listed as .449 or .450.
One other thought……
The headers looked to me like they may have been 2” hookers.
If they were 2”, then something smaller would have probably picked the peak TQ numbers a bit.