> A part of a product I worked on was killed by the business and outsourced instead. I’m 100% sure this was in fact because of technical debt, even though my team members would disagree.

I've also had this experience, where a product accumulated so much tech debt (in part, due to my decisions) that it was simpler for the business to outsource the functionality. That wasn't the only reason, but it was a big one. When tech debt sand gets in the software delivery gears, the allure of vendors increases. Sure, the business won't get things exactly like they want them, but they won't have to deal with missed deadlines and degraded functionality either.