It really depends on the type of applications you are going to create. Many businesses are already using Streamlit to rapidly create internal tools and dashboards. If the code is well optimized, the Streamlit app will run smoothly in a production environment. You can read the viewpoints of other developers building business apps in the link provided at the end.
If your goal is to create consumer-facing apps, then a better user experience and user interface will be preferred. In that case, JavaScript-based frameworks will be a better option to achieve full flexibility. However, it will add additional costs, deployment, and maintenance overhead.