Ah yes, the classic interview fairy tale where bosses claim "we don't have technical debt" with a straight face. That's like saying "our codebase is flawless" or "all our documentation is up-to-date." The detective's doubt button might as well be a nuclear launch button at this point.
Every company has technical debt lurking in the shadows. It's either hiding in that legacy system nobody wants to touch, or in that "temporary fix" from 2015 that somehow became permanent. The only question is whether they're honest enough to admit it or if you'll discover it on day three when they ask you to "just make a small change" to the monolithic spaghetti monster powering their entire operation.