Yeah, but it's vim.tiny. They don't even alias it to `vim` because it's not full vim.
Debian Stable (without a DE) only comes with nano AFAIK.
I'd bet good money both ed and vi are there as they are specified by POSIX iirc.
It has vi in the base system, specifically `vim-tiny`. Vi is mandated by POSIX, so pretty much every distro includes some minimal version of it in the base system. `nvi` is also used sometimes instead.