I think the problem lies deeper than that.
Moyes tried, LVG tried, Mourinho tried and we're still shit at attacking, something is fundamentally rotten with our players' mindset. I don't think it's that simple of Mourinho didn't tell them to attack. And that's not me defending Mourinho, I just don't think the next manager comes in, lay out his plan and suddenly we're transformed into a free flowing football.
I give you Moyes probably just a bad manager, but LVG/Mourinho aren't stupid chumps, if they can't make us work then IMHO there's something wrong it's more than simply them not being told to attack.
Barcelona / Madrid changes manager almost every 2 years, but their attacking football remains intact. We changed manager every 2 season and we're still miles behind.
Put mourinho managing City he'll show some attacking flair, but put pep in our current squad we will probably be served with the same shite of disjointed football. Swap Mourinho with Zidane/Klopp/Pochetinno and he'll have a capable working squad while the swapee will look clueless managing our squad.
You might not believe it, but god forbid mourinho is sacked I bet the next manager whoever that is won't fare much different than him.