RE: Mean: Is that a valid management style?
Sometimes it is.
I have seen evil, wicked, mean and nasty used to drive out executives that can be (charitably) described as "entitled twats" after a change of ownership. The new owners wanted to send out a clear message to the employees: do your job, or else.
For those that showed up every day, did their best despite the laziness, indifference and effects of manglement, they had little to worry about. But manglement, feeling entitled to working from home instead of going in to the office; it was a wake up call.
The general opinion of manglement was that they (manglement) believed it was OK to FOAD, and collect a paycheck for doing it. Manglement felt that the previous owners basically "gave them the company to run", and they chose to run it into the ground, instead of doing their jobs.
Meanwhile the other employees busted their asses keeping the company running, and finally, the former owners got tired of the lies and excuses, and sold the company quietly.
Did the shit hit the turbine blades the morning the new owners arrived!!!!
For each executive in the list, the response was the same: "Working from home."
That did NOT sit too well with the new owners. They consulted their lawyers, and then unleashed hell on manglement, which occurred one morning when the asset recovery agents showed up at manglement's homes with court warrants and sheriffs deputies. The warrants were for all company property and documents at that residence. Those agents took their sweet time tearing up the place, looking for everything.
Manglement was told that in no uncertain terms, their work from home privileges were abolished, and manglement better get their lazy asses into the office.
The next morning, they got sacked without severance pay. When word of the sackings reverberated through the company, the morale problems started to disappear. The employees were no longer stuck with stagnant wages while manglement rewarded themselves with raises and bonuses for incompetence and laziness. It took less than a year for things to turn around.
 (in this instance) Fuck Off All Day