Totally right ! That's why I prefer /5 second hand valves cover than repros. Here, Europe, second hand and repros are at the same price.
Those at BMW dealer seems to be also chinese now
Old ones are heavier (more aloy) casting is better, walls are larger
Like many BMW parts quality is not at the rendez-vous like back old days... I think also about ruber boot on carb gas wire that are totally crap and last less than a couple month were the old ones on my Silver smoke had last maybe 20 years