Older generation fabs for major manufacturers (Samsung, TMSC, others) were heavily impacted by staffing shortages due to covid/lockdown/etc. When staffing is low, the new fabs run 100% and the oldest ones just shutdown.

This caused a bunch of chips that are old and cheap to be complete unattainable, due to a lack of safety stock across the industry. Cars, power supplies, and other "large" things are highly dependent on these older chips, and have very long redesign timelines.

Newer generation is actually simpler, its just demand growth outstripping supply. I'm sure 2020/2021 also impacted the ability to bring more capacity online but probably only to a small extent, these are long term investments that aren't responsive to instantaneous demand.