The side window visibility isn't all that bad in conventional trucks, if a driver takes the time to look. though there can be a blind spot if the driver doesn't turn his head and actually look to his left, and downward too.
It's the right-hand side which has the larger blind area...if a driver isn't always monitoring the mirrors...some dummy can sneak up into the right-side blind, then stay there. Changing lanes to the right is one of the more dangerous outmaneuvers.
But look at those tiny mirrors. How is a driver supposed to see much in those little things?
I know mirrors cause a lot of drag (old fashioned, so-called "West Coast" mirrors which can be flat. slab like affairs, about the worst)
But trucks need mirrors. The more the merrier, and a driver should use them all, all the time.
They’re probably replacing the mirrors with cameras? Maybe with proximity sensors like in the rear bumpers of late model cars?