Looking at things from the other side: being a manager and trying to sell projects to reduce technical debt is really freaking hard in a world of short-term outlooks and revolving door of CEOs that want to improve numbers this quarter or the next, not a few years down the road.

This is entirely true, but I have never worked with someone beyond the leader of my immediate who though the same. Most managers don't care what cruft is in there when it ships.