I liked the article, but I don't know if boxing is necessarily underated, perhaps by fans, but I don't think by the fighters themselves. Cain, GSP, Edgar are three current champs that use or used classical boxing, GSP more so as of recent, but Cain and Edgar certainly merge their wrestling/classic boxing as their primary arsenal and BJ Penn supposedly banked his reign on his marvelous jab and counter punching. I believe Mir got into boxing quite extensively as well, as far as fighters that go beyond the general term of striking, but train in classical boxing.
Granted, leg kicks and TD's are an obvious threat to a boxing high guard, but wrestlers or people who tend to throw kicks also have a very low arm guard which makes them vulnerable to proper boxing. It's all give and take. Good article though