[htns]

Think of it as memorizing 4 IPv4 addresses.

[Avamander]

In many cases big parts of the address are zeros, so it might be only one "IPv4" address one has to remember.

[lucb1e]

And common prefixes like 2a00:: or 2001::, not that many are in use (yet). And I prefer typing ::1 over 127.0.0.1 any day (though most software accepts 127.1 as well).