For 90% of your NIN life you only need 2 jutsus for ST and 2 for MT, and a simple 1 2 3 order for TCJ.
Mudras aren't rocket science. Instead of blaming the mechanic just try harder, because there are a lot of activities IRL that require way more memorization and coordination than that to make this anywhere near as this serious complex input as you're making it out to be.

If you're one of them "but i play to relax I want to shut my brain offf!!!!!" then just play another job. God knows this game only has a handful that appeal to players who like a layer of jank or skill floor to their playstyle anyway.