Here's why it's okay for The Immortal to be dating

People constantly complain that he's lived for several centuries and is therefore too old to be having romantic relationships. Which is technically true, but also not. Hear me out

When Immortal got his powers, he appeared to have stopped aging from a biological standpoint. Meaning that, while he has indeed been alive for a very long time, he never actually advanced in age. And while we don't know his exact age, I think it's safe to assume he was in his mid to early forties when that happened, which clearly is not too old to be dating

In summary, he has lived for several lifetimes, but since he stopped aging, he can actually considered to be way, way younger