S2 and C2 are not old versions of S3 and C3 (C2 isn't even released yet), they are just cut down/lower cost version (but also with some added features for low power operation).
If it's a guide maybe you should mention that the original ESP32 is still for sale and still faster than some of the newer alternatives. There is also a new faster risc-v based variant without wifi/bt that was recently presented called ESP32-P4.
Some projects don't work with the newer boards (wled for example).
Partly this is because the Esp sdks aren't as mature for the newer boards. This is very true for the brand new C6 series, but somewhat true for th S3 and C3 lines as well