there were some incentives on these trucks, but mostly when they were discontinued...their push was to move full size, not compact trucks.
looking at the carcost website you linked, the Sport trim with automatic and FX4 package was a hair under $30k...aside from power windows/locks, V6, 4x4 and AC, it was basically a "basic truck"...no heated seats, no leather, no serious off road bits (like the ZR2 has), no infotainment, nothing...it was a nicely dressed 1980s truck...nothing wrong with that, but it's very different from what the ZR2 is...of course the new one is going to be considerably more money, it's considerably more well equipped...it's not like the new truck is $20k more and there's nothing there...there is a TON more in the ZR2 vs a top trim Ranger from back in the day.