Isn't the Ohtani rule that he does not count as a pitcher, towards the limit on arms?
I do think the notion that the extra player is a near replacement level in every organization so Ohtani allowing an extra roster spot has little/no value is too simplistic.
Even if the extra man is a replacement level reliever:
1) that could mean less stress on your GOOD relievers, increasing their production
2) that could mean you get to have valuable MLB looks at promising replacement level players. So some benefits in development, or roster churn.
Like, I bet the Rays would benefit A LOT from having a player like Ohtani.
A team could literally use the "extra reliever" as a waiver claim churn spot. If the team is any good at hunting for gems, once in a while that "extra guy" could end up as a real bullpen dude.
But the Angels are benefiting NOT AT ALL lmao. Because they suck as an org.
So the extra roster spot could be worthless for the Angels and all bad orgs, but could be valuable for a smart org. I think.