If you're working on a talented team, there should be no presupposition that the tech lead is necessarily the best developer on it. But you should be good enough to break ties and set direction. I've worked on a lot of teams with talented developers who aren't especially interested in leadership, or former leads who've decided they want to go back and hack some more. You cannot, and should not, boss these people around. But you can block management up, and unblock team down, by keeping management out of everyone's hair, and keep the developers from tearing each other apart over complicated technical questions or obscure business ones.
If you're working on a team that embraces pairing, that can ease a lot of the pressure on the lead to do reviews as long as the pairs are well-chosen. Trust but verify.