With all due respect to Mike Mearls, he is wrong. The action economy in 5th Edition is beautifully designed, and I wouldn't change a thing about it.
Action economy discussions are just the latest iteration of weapon speed factors, spell casting segments and "but I can do more than that in sixty seconds!" debates of AD&D. Please, with the "role-play" vs "roll-play" moralizing.
Our 1e/2e games didnt and dont have this issue, but we use a modified version of Moldvay Basic with each side rolling d6, higher roll wins, ties are simultaneous.