Especially on national and international broadcasts.

You expect homerism with local broadcasts, they're catering to their demographic. Jack Edwards is one of the most hated commentators in hockey, but he calls Boston Bruins games for the New England Sports Network. You expect him to favour the the Bruins, pretty much everone watching the NESN broadcast is a Bruins fan. But he doesn't call the Stanley Cup Finals for a reason.

But on nationally televised broadcasts open bias is quite frankly unacceptable. Major League Baseball fans saw it this year with the AppleTV games (fucking horrible idea but I won't get into it). Not only were the commentators pretty subpar, their biases were obvious. Big market team good, small market team bad. It fucking sucked.