[spion]

If you take the time to read about it, you'll quickly realize TIOBE is pretty bad.

[sandov]

What index do you suggest instead?

[spion]

To start with, I would try to fix the list here https://www.tiobe.com/tiobe-index/programming-languages-defi...

as well as adjust the query for programming-specific engines like GitHub. To have a programming language index not even consider github or stackoverflow as primary sources makes it a laughing stock IMO