Newer fancy things like code completion are a little faster, but the thing I care about most in my IDE is if I can command+click for type definitions.
For example, writing Python scripts for Fusion 360 modeling is almost impossible if you aren't able to find all the methods and type definitions as Autodesk's documentation is pretty terrible and doesn't list most methods.
If your IDE doesn't have type definition support, being productive with certain APIs with terrible documentation is impossible.
If it's all vanilla code, then this isn't as much of a problem. So the need for better IDEs comes with more complex code.
For example, writing Python scripts for Fusion 360 modeling is almost impossible if you aren't able to find all the methods and type definitions as Autodesk's documentation is pretty terrible and doesn't list most methods.
If your IDE doesn't have type definition support, being productive with certain APIs with terrible documentation is impossible.
If it's all vanilla code, then this isn't as much of a problem. So the need for better IDEs comes with more complex code.