Corrugated plastic underbelly?? Is this normal??

I'm new to the camping world and have been looking more at my 370 bhq and notice how flimsy things seem to be with this camper.
But my question is if most camper underbellies are made like this because it appears that a cheap sheet of plastic " garage sale sign " material is used to protect all the components under the camper and if this can rip off while driving.
Is this the norm?