What are the downsides of a twisted wheel?
You are lucky to have V-brakes, because they make repairing the wheel yourself an easy half an hour task. Plus the tool is $2 usually.

Spokes pull the rim one way or the other (look at the spokes and their angle from the hub flange to the rim). If you tighten a spoke, it pulls the rim away. So, you 1) tighten your brakes barrel adjuster until they rub heavily 2) tighten the 2-3 spokes around the dent to pull the rim away 1/2 or 1/4 turn and loosen the the same amount the spokes, pulling the rim the other way 3) repeat many times, until there is nearly no rub 4) loosen the brake's barrel adjuster to the normal riding setting.

If you don't fix the wheel, it will be easier to get damaged the next time. That's it.