Oh yes, he is an outdated ninja. One time, he was used to face naruto SOSP user (fear from passive disable standard attacks).

From my sense, he is not usable in the current meta because:

- Lack of immunity. Sure, you c*e root of warrior from LM, but there is possibility of it being removed (by ETR madara for example).
- The need of chakra to scale and spam mystery is easily countered by ETR madara barrier.
- Fear is not even guaranteed.
- Lack of useful debuff such as immobile to stop opponent. Other alternatives are: increasing mystery cooldown, increasing chakra usage, or absorbing chakra, but he doesn't have any of the mentioned. Although, irremoveable paralysis on his standard can be useful in some cases.
- While his mystery break super armor, it can be dodged easily by dodging ninja. Using him as P1, you would expect him to move the first, but it is not possible if your opponent dodges. He is not effective to use against ninja who dodges.

Overall, he would likely be a support who is utilized for fear debuff and irremoveable paralysis rather than a P1. The problem is, he is not the only choice. He is a generic support that doesn't support any units specifically. There are plenty of alternative which could help you more in the current meta.

The simple answer is they didn't want to make a it a position 1 sasuke with it,
The skill set is definitely more a support meta unless it gets to survive and scale tons.