Django's biggest issue is their aging templating system. The `block`, `extend` and `include` style of composition is so limited when compared to the expressiveness of JSX. There are many libraries that try to solve Django's lack of composition/components, but it's all a band-aid. Today, making a relatively complex page with reusable components is fragile and verbose.
The second-biggest issue is lack of front end integration. Even just a blessed way of generating an OpenAPI file from models would go a long way. Django Ninja is a great peek at what that could look like. However, new JS frameworks go so much further.
The other big issue Django has _is_ solved by Cot (or Rust), which is cool (but not highlighted): complicated deployments. Shipping a bunch of Python files is painful. Also, Python's threading model means you really have to have Gunicorn (and usually Nginx) in front. Cot could have all that compiled into one binary.