Apple seems to be doing that just fine and with huge success. They are exceedingly good at silencing every single employee to not speak about any kind of internal dissent or HR issues like this.

Perhaps, but hiring skilled researchers who do not think they need to say whatever they want is probably not as hard.

Importantly, Google offers great work conditions, access to their intellectual property and different evaluation criteria. Many prefer that and other benefits over the stresses of a proper academic career.