I have three young adult sons—one way to prevent this age group from doing nothing all day but video games and porn (maybe the only way) is for parents to decline to allow them to live at home after age 18 (except for during college summers and short term emergencies).
My kids all can live at home as long as they need to. My 20 YO lives at home. He’s working a good job and saving money for college.
I’ve made it clear for years to all my kids that they can stay at home as long as they want but I won’t tolerate them doing nothing. They have to be working or going to college. The minute they stop either, is when I tell them it’s time to move out, and I will do it. Loving your kids is holding them accountable.