When considering claims of Jets fans, it's best to go back 2 years. Yes, sometimes over-optimism presents itself during the down times of the previous season or during the winning offseason. But true optimism for the Jets is always 2 years away. In this case, the lure of a top draft pick QB who is bound to be on the road to superstardom in his sophomore year. The chance to improve those (few?) weak spots with a couple of new draft classes.
Then reality sets in. The QB has underperformed. But there's hope - a small stretch of games near the end of the season can be taken out of context and made to look like he is indeed the savior! Until he plays the first week the next season.
The draft classes are so bad that the Jets have the fewest drafted players (15 according to MNF, 14 according to The Ringer) of any NFL team. And their 3rd round pick was almost inconceivably cut before the start of the seaon.
Remember, optimism is not for the current 2019 season or even the 2020 season. For the Jets fan, the true optimism is for the 2021 season.
And on it goes.