Who cares how it was composed or if you consider it "corporate rock." It doesn't invalidate it for me. In '67 "hacking" was routine.
Whatever Cherry Cherry was moved people and defined a sound and style for 20 years. Mellencamp, Paul Simon, The Romantics ('What I Like About You') etal., ALL ripped Cherry Cherry and Diamond off.
Btw, who hasn't "borrowed" from anyone else? The Beach Boys routinely ripped Chuck Berry off; So had The Beatles.
Anyone who's been listening to music from the 50's till now knows what "Real Rock" is. FWIW, I don't need someone else's ear to define it for me.
“I’m a Believer” alone is proof that Diamond had the songwriting chops worthy of the RRHOF.