Ask HN: Why do we still buy cars like it's 1995?

Recently tried to sell my car and was shocked by how archaic the process remains. Facebook Marketplace is sketchy, Kijiji and Craigslist are dying, and dealerships take massive cuts. Airbnb revolutionized home rentals for a $1T market, why hasn't anyone cracked the $1.5T used car market? Is it regulatory capture by dealers, or am I missing something obvious?