Yea, you are very much correct on this bro, the high level of inconsistency is the major difference between arsenal and Manchester city side that has won the English premier league title in the past four seasons if am not mistaken, because the quality is also there in these arsenal team, but they are just too inconsistent to compete.
Biggest difference between Arsenal and Manchester City is their experience in Premier League title competition. Arsenal only joined it in two latest seasons, and this season is a third one after many years they struggled to finish with a position in top four. Manchester City in contrast have been joining a league title competition in many seasons and not only participate in it, they won many titles.
They have won 8 Premier League titles in following seasons, and since 2017 - 2018 seasons, they won 6 titles in 7 seasons. Arsenal can not compare with Manchester City in terms of experience.
2011–12, 2013–14, 2017–18, 2018–19, 2020–21, 2021–22, 2022–23, 2023–24
https://en.wikipedia.org/wiki/Premier_League