Am I reading this incorrectly or author is equating "using old/boring/forgotten techs" as technical debt? How did technical debt become so bloated and meaningl

Am I reading this incorrectly or author is equating "using old/boring/forgotten techs" as technical debt? How did technical debt become so bloated and meaningless? Isn't it "remaining half baked/incorrect code, known edge cases, bad/slow implementations, or even bugs due to constraints imposed on the engineering team"? How is dead technologies are imposed constraints? Author is not talking about technical debt but experience that is not directly applicable anymore.