there was a recent article detailing why jet engines are so hard to do, and that the US was one of the few countrys that maintained the very complex and precise layered knowledge and manufacturing base to make the hot section blades and the arcane methods to keep even those ultra tough and durrable parts from melting or breaking. To put it into perspective, every last thing in your home or business would be burnt and destroyed very quickly if exposed to the conditions inside a modern jet engine, including titainium and ceramics. From my perspective I can see how under current management conditions it would be easy, very very easy, for some bro to wreck decades of acumulated knowledge and practice and never even know, and his "superiors" to never know, just that there is now a problem with something™. And they also dont know that in mechanical engineering of aircraft the first law or aviation is that everything effects everything else , which requires some things to operate at there limits, meaning that changes or substitutions will fail the whole aircraft, or create havock for maintenance, etc, etc, etc. No Bros, bro.