Szymon

I would argue. You forgot about very important thing. And precisely, that Isshiki was reincarnated in a incompatible vessel and in addition Amado stated as if it was not like this, it would be impossible to defeat him. Even Naruto in Bayron Mode could not be able to beat him because its a limited duration. He could give him a damage but Isshiki would be straight up to regenerating himself. In this case he could even to show tehniques even more powerfull than he did in reality fight and which he did not want to use because of risks from lost more time.

That was fight from time not from opponent. 

Jura will have to show for really powerfull abillites and ways to use them to be thought like someone really stronger than Isshiki. I don't doubt he is able to it but if we say about Isshiki in Prime or Full Power, has not to easy task. Of course, if he has similar to Goku ability for unlimited potential to grown in strenght by evolution, there is nothing matter.