That respirator bag may certainly be crap workmanship, but here it is 70 years later, still in usable condition. Probably made by very basic skilled workforce, and done 'under the pump' time wise. God forbid it should ever be needed again.
If you reckon that's lousy.................you should see the quality of panel fit on CMPs! No wonder they are full of stress cracks.
Guess dodgy workmanship is nothing new, just occurs for different reasons these days.