It isn’t dumb to go after a guy like this. I don’t know the details of the battle, like what was spent, and when, but it may have been a very good tactical move, and it almost landed you a big fish as a C program. More guys should take shots like this.
UConn was in a position to keep you (and possibly Arkansas, too) out of signing range. They didn’t prioritize the recruit highly enough to do that, though. I don’t know what happened in this particular battle, but what you often see is a team like UConn shows up, gets a scholarship in fast, and everyone bails, like pallas says. Then it can go a couple different ways. If UConn gets comfortable, they may go try to lock up other recruits. Maybe they drop AP, maybe they neglect promises and/or visits, etc. In that situation, you could be in a great position to steal a guy. Of course, they may still have plenty in reserve to come back and overwhelm you, if given enough cycles, or someone else (like Arkansas) might have the same idea, so there are always risks to this strategy.
In this case, you were the effort credit leader when the guy signed. You were in a good position, and you clearly invested a lot more resources than the other two teams, but their prestige and preference advantages kept them in range, despite your prioritization advantage. It wasn’t a dumb play. You made a choice, you took a risk, it didn’t pay off this time. Calculated risks aren’t dumb. It’s only dumb if you don’t understand the situation, and the possible consequences of your choices.