i think that like anything else, there is good and bad in any manufacturing process.
maybe back years ago, as in what the video mentioned, "air bubbles" may have been the issue that caused things to break, whether they be plastic or metals.
i think that todays metallurgy and reduction of "air bubbles" and void spaces are not so much a worry anymore.
in any event, it could be some time before people see that a casting can be every bit as well built as forged.
i look at it this way too...
i have "plastic" 45 ACP guns......
shouldn't "plastic" guns explode from the hard stresses of 45's..??
afterall, aren't they "injected molded" as well??
aren't there "air bubbles" or viods in that process as well??
yet people are buying "plastic" 45's, even i have 1 now, a G-30 and hopefully soon an S&W MP 45 ACP.
i have "confidence" in today's build process of casting metal, and "plastic", more so than i ever would have, IF i had started this sport/hobby, 20, 30, maybe 40 years ago, compared to todays improved processes.
let's not forget too, how did those cast frames explode, or crack.??
hot reloads..??
we have also all "seen" factory loads that have caused a few issues to....right..????
in the end, it is what it is, for personal experiences and opinions, then too, this debate can go on an on, with subjects like vehicles built back in the 50's, compared to today, with better oils, fuels, emissions systems, fuel milage, ride comfort, and more safety features to survive a crash, than ever before.
yet, someone who lost a family member in a crash back in the 70's, with far less safety features, still wouldn't think so.