> I fear bike manufacturers are switching to less repairable

Is the frame really an issue though? I don't aluminum frames break that often, I'd bet that's probably one of the least common problem for modern bikes (gears, brakes, suspension etc. are way more fragile). Most bikes are likely to be discarded way before the frame would need to be repaired. It seems totally like a red herring to me..

> Steel framed bicycles are good enough for the vast majority

Well most people don't seem to agree. There are still plenty of steel bikes available, even relatively high-end ones, they are just not that popular.