The problem with bottlenecks (funnily enough, a topic that we're now talking about more than the short-faced bears over on SA) is that unless you're at max production, there's
always a bottleneck. Fix that bottleneck? Now something else is a bottleneck. Sometimes multiple things at once. Tesla has repeatedly cycled through bottlenecks as each time they fix one thing, something else comes in. First it was frame welding automation. Then the big long-term problems with battery pack production. Then paint shop. Then general assembly. Then paint shop again. Occasionally its been suppliers limiting them. Now they're hitting up against Giga's cell production limits - not sure whether that or paint is currently the limit. Things will just keep switching, and that's inevitable during scaleup.
Interestingly, I've never heard of stamping or plastics being a bottleneck. I guess Tesla has that part down