cheapest speaker made in the last 10 year that can beat any speaker made before 1970?

Can't answer because "cheapest" is not defined, speakers choices are subjective and are of different designs (box, horn, panel, open baffle...) so would be comparing apples to oranges.

Question seems pointless because it's always what your personal preferences are limited by budget aka it's whatever best speaker YOU like within YOUR budget.

How do you compare a panel speaker to a box speaker?  They have different advantages and disadvantages.  

a stand mount vs a floorstander?  Apples to oranges or rule out stand mounts?

if you’re speaker shopping, a budget, stating your audio chain, and sonic preferences would be much more straightforward.