In its August 2007 review of flooring, Consumer Reports said this about
solid wood flooring: "But ... all tend to dent."

In the rating table, they state that prefinished solid wood was "mostly
oak, typically nailed to a subfloor, and all were 3/4" thick."

Red oak has a Janka hardness rating of 1290; for white oak, it's 1360.
Hard maple, rated at 1450, is only about 9% higher than average of the
two oaks.

So why can bowling alleys, typically constructed of maple, withstand at
the approach end the extreme abuse of dropped 14-16-pound balls so well
while CR claims that all solid wood flooring tend to dent (even under
the relatively less severe conditions in a typical household)? Thickness
can't be the answer, because dents are surface phenomena. I can't
imaging thickness greater than 1/2" inch being any more dent-resistant.

As an aside, the report also said engineered wood "dents easily." This
makes some sense; if you put a thin hardwood veneer over a relatively
soft under layer (as an absurd example, balsa wood), the veneer won't
have any support.