The most useful jutsu of all would be kage bushin, without any doubt. It can be used in ways to make everyone happy.
If you are a perv, you can spy on more girls
If you are a player, you can get more girls.
If you are a criminal you can rob a bank by yourself.
If you are a soldier you can have an insta army.
If you are normal, you can shop, hang with friends go to school, and chill at home, and go to work, and do chores all at the same time.
If you are a daredevil, you can do any stunts, even ones that kill you, you can do.
If you are greedy, you could work many jobs, all at once, and get paid a ton of money.
If you like to learn. you could learn a language in a very short time.
If you like to take over the world, you could make a small army and take over several small countries, and then join them toghther and begin your conquest.
If you like to kill zombies, you could have your clones act like zombies and you can kill them.
If you want to build a house, you could do it in just a few days.
The possibilities are endless. Now that said, there are still plenty of jutsu out there, that people like, but shadow clones is the best jutsu for people, as it has the most uses.
But to each their own, simply kage bushin, is a very useful and versatile jutsu, that could help all people achieve what they want.
