no while they both very similar, theres nuance to it.
- Peerless highlights a lack of comparison due to exceptional qualities.
- Unrivaled focuses more on the absence of competition or challenge.
while the latter can be a consequence of the former, the former highlights something being exceptional initself not simply because of the absence of another
the base shibai in question is a fruit away from being peerless is significantly more impressive than one who isnt like ishikki
ishikki could have eaten quintillions of fruit, and it would still be vastly inferior than being a fruit away from ascension, so unless we have a direct number for how many fruits are required for ascension or a statement that says the next fruit that ishikki would have eaten would have ascended him then theres no reason to compare ishikki to shibai.
naruto's case is contextual and refers to the chakra naruto produced himself (as in the raws) Ishikki's only claim to fame is being above everyone in the present, which barely touches the cosmology and one off statement from anime promotional episode where he is "the strongest/fearsome enemy"
this isnt even a good statement either but thats not here or there, but even so i dont have an issue with Ishikki or baryon mode scaling above the ETSO , what was rejected before was the methodology in how one goes about it because it creates issues.
shibai isnt ishikki nor is he the MAS