A couple of weeks ago on this thread, someone said there was no shortage of passive components. I disagree.
I took a look at one of my designs that my purchasing guy is having trouble with, and ran it through a BOM tool at one of the major US based distributors. It's a large design with a lot of line items.
Integrated Circuits: 30% in stock
Resistors: 42% in stock
Capacitors and Magnetics: 44% in stock
Discrete Semiconductors: 60% in stock
In normal times, I'd expect at least 95% of these parts in each category to be in stock.
For discretes & jelly bean it's rarely a problem to sub. Even in the depths of the cap shortage period, it was possible to figure something out without having to resort to a respin.
The problem with chips is that nowadays there is no second sourcing. The best you can expect is to find a device in the same package with more flash for example, that's an approach I've resorted to even in good times. Or you might have to change package & do a respin, but I suspect it'll only be a short time before that package dries up too.
There seems to be two strands to the chip shortages.
Firstly, the devices with sporadic availability, where I suspect the wafers are already made and in storage, but are awaiting dicing & packaging.
Secondly, there are the devices with long term unavailability, where they're still waiting for wafer fab availability.