I'm not sure I'm following? According to ODOT, Kelly is classified as an urban collector, which according to the table roughly translates to `highway=tertiary` or `highway=secondary`. Given that it doesn't have a light at Powell and has a 4 way stop at 8th, it can be reasonably concluded that `highway=tertiary` would be more appropriate in this case.

Regardless, functional classifications from ODOT were used as just a starting point for determining highway classifications on OSM. While the goals of each roughly align (funding and regional importance respectively), there are places in which these differ.