Back. Your. ****. Up.
https://www.news4jax.com/sports/nfl/jaguars/myles-jack-reaching-potential-in-year-2-with-jaguars
I didn't deny anything last year, last season is irrelevant at this point. He was a rookie in rotation - it's not about making mistakes, it's the fact that Smith looks absolutely lost, baffled, avoids contact, and still looks as though his knee isn't right and we have no idea if it will ever be the same.
Nowhere does it indicate that Jack "bombed out" - like you are stating. He has been given more of a role this year, to the point he's been allowed to command the other players (as mentioned in his article) - the HC loves him and praises him.
And I don't think ONLY Jack would have made this "noticeably different" - which is why I mentioned Ramsey and Collins, both players many here wanted on draft day. Instead we chose gym rats and jersey sellers.