I think you’re not giving him his due credit. He may only be fixing there devices, but that gives him a unique perspective on how the design behaves in the fiel

I think you’re not giving him his due credit. He may only be fixing there devices, but that gives him a unique perspective on how the design behaves in the field. Having watched quite a lot of his videos, he is, at the very least a competent electrical engineer, if not a formally trained one. On top of explaining a problem, he narrates why the problem is happening, which is indicative of solid understanding.