75 problems carry locked into the old system

The hard part isn't inventing the new thing; it's that the old thing is everywhere. New encryption methods are ready, but billions of devices have the old one hard-wired with no update path. Better building codes exist, but the certification ecosystem grew around the old ones. Factories, vendor ecosystems, and forty-year infrastructure all defend the status quo through sheer sunk cost. Solving these problems means designing the transition, not just the replacement.