No, it's not, and your exple is wrong.
The example is correct.
Uefi boots after cpu and ram are initialised,
No it doesn't. Uefi handles the entire boot process, the first opcode executed by the cpu is part of Uefi.
then it initializes other hardware (such as drives) mounts partitions, and boots the os.
The firmware inside the Tegra does the same.
Uefi can't boot without ram.
It should boot enough to tell you that you have no ram.
And also, you got cpu microcode, which is a very small firmware that initializes cpu at the very low level and translates opcodes into machine language.
That isn't part of Uefi, it's an implementation detail of the cpu.
It doesn't do what you think or work how you think.
It's not like a piece of code that runs at startup to initialise the cpu, it's only called in specific circumstances. Like when a complex instruction needs to be decoded, simple instructions are hardcoded. It's nothing to do with firmware at all and isn't considered firmware by anyone.
Switch, on the other hand, doesn't have this dedicated spi flash chip,
That is an implementation detail & irrelevant. Uefi doesn't need to be stored on a flash chip, it could be stored on an SSD and loaded into some ram by dedicated hardware at bootup or it could be embedded into the CPU. Intel decided to store it one way, Nvidia decided to store it another.
Rcm on the other hand is like part of cpu microcode
No it's not, you clearly don't understand what microcode is.
Also SoC firmware, which contains rcm, is read only and can be flashed only while manufacturing.
Actually the hash is read only, you could apply patches to it if you could get a hash collision. Then you could patch out the signature checking & just patch the OS on nand to give what could accurately be described as CFW.
all software elements which make this systems work (all loader chains, OS and preinstalled applications) usually called firmware
Some people call it firmware, even though it isn't called that by nintendo & doesn't meet the industry standard for what firmware is.
The parts of the "system" (as nintendo call it) that atmosphere replaces is not any part which anyone would describe as firmware. Atmosphere doesn't install in the same way as the official updates either, which is how typically CFW is differentiated from a jailbreak.
Just look at PS3 scene evolution of PSJailbreak, CFW and HAN. The PS4 doesn't have CFW either, even though there is little conceptual difference between Atmosphere and the PS4 hen.