Overrated in MOST cases (not all)
Scenario One -
Emergency Plumber, has an OK site that's ranking pretty well because a lot of people reference him, he has good reviews and he's clearly good at what he does - Bounce rate = 65% - You know why? Because people who call him are standing knee deep in their own crap, they want a plumber that's good and they've found one, they jump on the site and click to call him. SEO Done.
Most people want to contact him, not read about the latest pipe work fashion
Scenario Two -
Local councils - Everyone knows them, not always on a .gov website these days, all they want is a phone number or to pay a bill online, which in most cases goes to a third party website - 70% bounce rate
Scenario Three -
Car mechanic - Again, people want to contact them via the phone so they click to call, book a time for the car to go in - 70% bounce rate
Scenario Four -
Writer - The writer produces an awesome tips style content in the form of a PDF or infographic. Most of it is either people sharing to another website or downloading it for a later date to read - Bounce Rate 62%
Scenario Five -
A software developer is giving away software, its free and its simply grab an email, everyone is going nuts and sharing it.... 70% bounce rate but he is banking it
So in most cases, if you know there is a reason why the bounce rate is high then Google will most likely work it out. However, if you are producing guides, blogs and full-blown articles where you expect people to stick around then yes, bounce rate is bad.