Is the modern mindset like the Epicurean 'eat, drink, and be merry' mindset?

Yes. The modern mindset is described as becoming much like the Epicurean outlook: eat, drink, and be merry, with no thought of eternity. It focuses on instant gratification and what is in it for me today. Paul says if there is no resurrection, people may live that way, but there is resurrection.

Les explains that the Epicureans held the mindset of "eat, drink, and be merry, for tomorrow you're going to die anyway." They had no thought of ever meeting God or of eternity, viewing people as animals here today and gone tomorrow. He then says this is becoming pretty much the mindset of our own nation today: most people are not thinking in terms of eternity but of what's in it for me today, instant gratification, and how to gratify the flesh fastest and easiest. Paul says if there is no resurrection, then have at it, because that's all there is; but there is resurrection. The admonition in 1 Corinthians 15:33 is "Be not deceived. Evil communications corrupt good manners." Les also directs listeners, especially young people, to Proverbs 13:20.

Is the eat, drink, and be merry attitude of the Epicureans present in America today?

Yes. That Epicurean outlook—living for pleasure, tomorrow we die, no eternity—has become largely the mindset of America today. People pursue instant gratification, asking what is in it for me now. Paul's response is that if there is no resurrection, then have at it, but there is resurrection. Evil communications corrupt good manners.