1. Yes, everyone cancelled orders and idled capacity. Everyone was anticipating a deep and long recession until the fiscal/monetary bomb of March/April 2020. See #7 above.
2. The 120nm legacy nodes and similar are right at the center of the whole shortage. This has been underinvested for years because it has been low demand growth and low margin. Automakers are particularly vulnerable, because for years, every new feature has gotten its own cheap microcontroller to run it. There are now dozens in new cars.
3. Graphics cards have been affected by crypto miners sucking up supply at any cost, and everyone not named “Apple” competing for TSM’s top end processes.
4. iPhones don't just come with Apple A-Series chips made on TSM’s top-end node, but a host of others, some made on legacy processes where the shortage is. Likely we are talking about some cheap analog power chips or something like that. Apple has decided to push as much supply chain problems to iPad as they can.
5. For the vast majority of what automakers want, 7nm is overkill. Once there are more high end SoCs running multiple systems including self/assisted-driving, that will come into play. But that is not where the shortage is concentrated.
6. Apple was Intel’s 4th biggest customer before they left, so it has had a small impact, but only at TSM at their top node. Samsung has picked up Qualcomm and AMD as a result.
Crazy times in the semi world.