Yeeeeaaaah... that's not how that works. Legacy processes are often difficult or impractical to transport between fabs at the same node, much less fabs at different ones.
GP is saying you get the same functional performance as older chips for less size, power, and cost. Nobody makes main processors in 22nm anymore, for instance. That’s basically what was used in production 10 years ago for processors.
Nobody makes old processors (except for legacy support) because Moore's law has been a thing for 50 years. It has always been cheaper to produce chips at scale with the latest tech. This has justified the creation of 10 billion dollar factories, till recently
Now that the law is close to coming to an end, the economics changes. Latest tech provides negligible marginal benefits to the median consumer. So now it is possible to think of commodotizing a single process and making the factories much much cheaper.
'Main processor' meaning the SoC used in a modern high performance device. Phones, tablets, or computers.
Plenty of lower power or older stuff (RPI included) use older nodes just because that's available. Microcontrollers tend to use higher nodes (22, 40, or 55nm) just because they don't need the super high speed stuff.
Also, the RPI5 uses 16nm, not 22nm. Still not modern, but not unheard of for stuff like SBCs where performance is not particularly important compared to cost.
People do that too. Fab ports to smaller nodes are something that absolutely happens, especially as older legacy nodes close down. It happens all the time.
