> As an example, if you had a software that was written 20 years ago to store data in a relational DB, updating it to work with current versions of that databas

> As an example, if you had a software that was written 20 years ago to store data in a relational DB, updating it to work with current versions of that database system won't be much work (if any). If you rely on managed services, I wouldn't be too sure that you get away that easy. This very much depends. In the example you gave, nothing changes if you used managed services or not. But you could argue that the 20yo software is technical debt preventing the upgrade of the database due to the source code being lost, the library used to connect to the latest version of the database doesn't exist requiring a rewrite in a moderm language or framework. Etc. Technical debt really is about code that cannot easily be modified to adapt to the requirements of a business. If you wrote some code, and it was trash, made no sense, in an obscure language that few people know, with no comments. Yet it ran for 10 years flawlessly with everyone too scared to look at it, but made the business money. It's not technical debt until it needs to be changed/modified.