Everything I see says the M2 family is 5. Vanilla, pro, max, and ultra.
The nm process for each CPU is listed in technical details on cpu-monkey
Rumors before the M2 release said that it used 4nm.
https://www.macrumors.com/2022/03/10/m2-macs-with-tsmc-4nm-process/
Apple says they use “second generation 5nm technology”
TSMC’s website says they have 6 different 5nm nodes: N5, N5P, N5A N4, N4P, N4X
https://www.tsmc.com/english/dedicatedFoundry/technology/logic/l_5nm
So the M2 likely uses N5P, N4, or N4P. N4 and N4P are usually called 4nm in marketing material.
There’s probably a leaker out there with more knowledge.
Not trying to start a debate, just saying the specs in the link were different than what was mentioned.
My point is that the M series transition went very well.
