I say the title matters - but not in the sense that it needs to tell you everything the book is about. Rather, together with the art, it at the very least gives a feeling. It's especially important when you spot the series outside of its genre, like when browsing a general "popular" section or as a poster at a convention. Though ideally the icon and art should speak for itself, they don't always, and the title can help with conveying the theme. It also is a part of your comic's general marketing and shouldn't clash with the art and story (intentional dissonance is of course a-okay).
But I also think that while the title not necessarily has that much power in drawing in people on its own, I'm convinced that it can do the opposite. In other words, it might not make the comic for a potential reader, but it can break it. Living in the German language sphere, I have seen so many horrendously bad German title additions to English movies that totally ruin the feeling and make them seem plain silly. For example the movie "Alien". A short title, to the point, minimalist. A very deliberate choice to make us curious. Now someone thought that there weren't enough clues in the title for German speakers or something. Maybe they think this language sphere is a bit more intellectually challenged or something. So they changed it to "Alien – Das unheimliche Wesen aus einer fremden Welt". Or in English: "Alien - The creepy creature from an unknown world".
Need I say more? /cringe
Oh and don't make the title hard to remember, like a long row of jumbled letters that are supposed to look cool but don't make a sensible word. While the title doesn't need to be genius, why make things harder for yourself?
