As regards all the brilliant psychologists here who are commenting "looks matter to most people!": it's not as though you will find every person you meet on ohmyperson unattractive. The issue is that meeting people you find attractive might happen less frequently than it would on eg Tinder. How much less frequently is an empirical question. It's worth noting that edited, filtered, selection-biased Tinder profile pics are not always useful. Sometimes they're worse than nothing. I've been on a bunch of internet dates in the past year, and half the time my date looks nothing like their photos. At least with ohmyperson I won't feel duped.
The problem I see with this model is that it might naturally lead to the situation where people develop a strong connection over messages and then feel disappointed when they meet IRL, only to find that they are incompatible for reasons of physical attraction. This happens sometimes and it's a real bummer. (It's for this reason that I think you should meet - or pass - after sending a couple messages, rather than having a protracted convo).
Just as the Tinder model provides a coarse grained filter for looks, I can see ohmyperson providing a coarse grained filter for interests, values, and relationship goals. Some apps (bumble, okc) have various filters for these sorts of attributes, but in my opinion none have really figured it out all that well.