Python's got a pretty incredible library ecosystem, and it's easy to get a project up and running quickly. The big problems with it start to appear as you cross

Python's got a pretty incredible library ecosystem, and it's easy to get a project up and running quickly. The big problems with it start to appear as you cross the 10k+ sloc / 3+ dev thresholds; if things are changing quickly, the iteration velocity the duck typing provides can quickly become a big problem. Type hints fix this by allowing you to ensure your contracts are upheld while your team continues to move. If you don't find yourself needing them, you probably don't have a team that's trying to ship and iterate super quickly, or your project is still at the one-off script scale.