So apparently someone on Reddit, leaked a few spoilers for the next few episodes, I don't know if it's true or not, but it seems exciting on what happens next:
If this is true, season 4 really can't be the end because it seems they are really hitting their stride more than ever. I think Gotham should end season 5 or 6. Especially based on the script that was leaked a while now. And CBR reminded me why I hate their lists, and why I like for the most part what Gotham did with Jerome and the Joker's influence even with the Twin trope they did:
https://www.cbr.com/dc-tv-villains/
My problem with this is that Jerome has been stated since season 2 as not being the Joker, and was a Joker red-herring from the beginning, and he is more like the influencing force/presence of the Joker of Gotham (not to mention there are a lot of time Joker has died or been assumed Jerome at the last minute was revealed never to be the Joker. Yes he has Joker traits, but he was always stated to being the foundation of the Joker legacy, showing how the Joker is more than a man he is an ideal which is showcased so many times. Also there is Jeremiah who just got introduced and is going to be developed in the next 3 episodes showing the influence Jerome has on Jeremiah and Gotham as well.
It seems like a nitpick argument automatically writing off Gotham's take on the Joker (And slightly praising it) before seeing how they actually present the Joker to be honest.