I agree that Barry and Iris were the OTP in season 1 despite Eddie, Linda, the ship teasing with Caitlin and the lack of Iris. But I disagree about season 2 WestAllen. They hammered home destiny only after Patty left because they needed a cheap trick to reintroduce the couple after they had done their best to sideline their connection and even retcon Iris' feelings. Season 2A was when you had characters like Patty refer to Iris as Barry's sister and her never correcting them. It was when Eddie was upgraded to the love of Iris' life when no-one called him that in season 1. Somehow he also became her fiancé even though he never proposed, she never said yes and never wore the engagement ring. I don't think Patty herself was ever written to be Barry's one true love but they absolutely attempted to raze the foundations of WestAllen and only went back to recentering them after the Earth-2 episodes.
Also keep in mind that before the Worlds Finest crossover AJK was gushing over the Barry and Kara chemistry and they are two characters who were never going to get together. Even Mehcad Brooks was talking about Barry hitting on Kara but where were those scenes? Where exactly did Barry hit on Kara? AJK got his actors to lie about scenes and oversell the Superflash dynamic.
It's true that many protagonists have multiple love interests before they settle down with The One but AJK went way overboard in my opinion. I didn't watch Lois and Clark but when OF were broken up I don't remember Oliver's temporary love interest getting more screen time than Felicity. Patty got way more than Iris and that was despite the fact that Iris knew about the Flash and Patty didn't. That's why they were being shady in 2A, not just because Barry got a girlfriend that wasn't Iris.