[davidmanze]

With long years of working in the field, or even without one, stuff tends to be dropped or banged around something. In my time, I've needed repairs for impact damage 4 or 5 times, and had at least three smashed filters. Several more with glass knocked out of alignment within the frame.

Just today when shooting on a construction site I've seen the gate swing with the wind and do a nasty thing on a chick photographer. She ended up knocked off her feet, bruised and at least the filter on her Nikon 24-70/2.8 got blown to smithereens. Maybe the lens is damaged too. Smartphone screen also likely smashed. The D4 (or similar) body has, conversely, blown a hole in the pavement, in all likelihood.  She had no hood on the lens.

For your particular use, a traditional removable hood makes more sense, indeed. Much cheaper to replace.
However, for more mainstream uses, I really think built-in hoods are very convenient.

Like when buying a car, we need customizable cameras and lenses at the time of purchase ;-)

 When staying in Barcelona a youth tried to steal my camera from my bag, the Samsung GX10 as it was then (Pentax K10) .........  fell to the ground, luckily onto the front of the lens-hood ...... I studied for damage and there was just a scuff on the lens-hood ........
  Realistically if you can afford the DA* 21mm F2.4 ....... and it gets dropped and bends the aluminium hood and barrel, rendering the lens unusable , no worries, it's likely you have the money to have the barrel and integrated hood assembly replaced ...... !

I mean that's what service departments are there for ..... isn't it ??

   dave's clichés