No, ssh is called by the local shell. ssh never gets to see the quoted value that you typed in your shell. This mechanism is unrelated to ssh, at all:
$ printf "%s\n" "asdf"
asdf
This happens as part of the shell turning the command string into argument vectors to pass to execv().
When I run:
ssh foo@bar "echo 'hello world'"
ssh chooses to unquote the string: echo 'hello world'
splitting it into two parts (echo, and hello world), and then running the program echo with the argument hello world.
The fact it does this via a separate program is irrelevant.
> ssh chooses to unquote the string > splitting it into two parts
wrong, ssh does no argument splitting
> then running the program echo
wrong, it passes the string to the users login shell, whatever program that is. See sshd(8).
> The fact it does this via a separate program is irrelevant
just gently caress yourself.
the fact that ssh chooses to invoke another program to split arguments instead of splitting arguments itself is a distinction without a difference.