Comparing TIOBE with Github octoverse, for the top 10 languages.
TIOBE: Python, C, C++, Java, C#, JavaScript, Visual Basic, Delphi/Object Pascal, Perl, SQL
Github octoverse: TypeScript, Python, JavaScript, Java, C#, PHP, Shell, C++, HCL, Go
Common languages: C#, C++, Java, JavaScript, Python
TIOBE only: C, Delphi/Object Pascal, Perl, SQL, Visual Basic
Github octoverse only: Go, HCL, PHP, Shell, TypeScript
Intepretation
SQL statements are usually embedded in another language, so github probably counts them in the enclosing language.
Perl and Visual Basic programmers don't use git, so github ranks them low. HCL files are probably deployed via git, so they appear in Octoverse
TIOBE ranks Go lower, because Go has better offline documentation (go doc) than other languages, so Go programmers don't search the web so much for API documentation.
TIOBE has a low rank for TypeScript, because TypeScript APIs are really JavaScript APIs, so people search for JavaScript
I don't know how to explain C's absence from the Octoverse top-10
Who uses Delphi/Object Pascal?