Unethical and illegal.
yes
To say that the Grand Canyon is nice is to understate its grandeur.
overstate
overstate, magnify
Minimize? Belittle?
Overstate, exaggerate.
Depreciate, minimize or understate.
understate, mute, tone down, subdue
In my opinion it is unethical.
To understate means to present something as less important, less severe, or to a lesser degree than it actually is. It involves downplaying or minimizing the significance or impact of something.
The unethical child was grounded for 2 months.
unethical competition in business?