In the end (current time), didn't they (Tesla) find a better way?
I am truly ignorant here, but based on what I have read, Teslas manufacturing process now is much more efficient/better than the standard GM/Ford, etc...
Tesla started from scratch and developed large-scale manufacturing and logistics from first principles. It was hard, but it's put them in a hugely advantageous position today. It turns out old-school manufacturing for ICE vehicles doesn't translate directly to EVs. Yes, Ford (for example) can build EVs, but they're not cost competitive with Tesla, because they're optimized for something else. Tesla produces 100x as many EVs as anybody else.
Now, was Tesla surprised by the difficulty of manufacturing, because they didn't know what they didn't know? Maybe, I have no idea. But in retrospect, it wasn't a mistake to ignore the accumulated wisdom of the car industry. It turns out the old-school companies don't know what they don't know either.
1. Elon thought they were smart enough to build cars with more robots and less humans than other manufactures. When this didn't work out, then swung to the other extreme and were employing far more workers than you would find at comparable plants.
2. Do you remember when Elon was tweeting about a national car hauler shortage, and that Tesla would start building it's own trailers? Tesla was the only manufacture having troubles with deliveries.
3. Have you watched the Sandy Monroe videos where they tear down vehicles? He has compared the build quality to 90's era Kias.
This is the same problem that plagues electric car startups. Most of these folks don't know what they don't know. Tesla has had great engineering from day one, but almost went under because it couldn't figure out large scale manufacturing and logistics. Problems that old school companies have been solving for a century.