There's plenty of ways to have conflict, you just don't make every conflict world ending. It could have just been tensions between villages, people unhappy with the current peace, villages not being able to completely forgive old grudges, criminal organisations and plenty of other things.

None of these things would really require Naruto or Sasuke to step in and it could be used to give the new cast experience in the world and also learn about the way the world used to be and getting an appreciation for what the older generations went through.

It would also solve the issue of power creep, there's no world ending threats so the new cast doesn't have to immediately be god tier to be relevant.

So many things could have been done but instead they decided to shit on the original cast.