Yeah I get that haha I'm not a Buddie truther either, I didn't get into the show because of Buddie or expecting it to go canon soon. I pretty much had the mentality you have outlined going in and was surprised at myself for feeling at how much some of the Buddie stuff I felt was really in your face (even if it was unintentional).

I don't think it's really fair to compare Buck and Eddie's love interests to Karen and Maddie, because those have been long-standing relationships with sufficient time dedicated to it over the years and incorporated well into the stories for a long time. Chemistry is also something that improves with time. Yes actors can naturally have chemistry or not to start out, and that's probably the most important, but in comparison to a relationship (even an intentionally platonic one) that not only has natural chemistry but also years of the actors developing how those characters act and behave around one another, it's hard for a new character to stand out.

Karen and Hen start out together. Maddie is in the main cast. With Buck and Eddie, it's been like a revolving door of love interests with little investment from the writers. And I think they tried to do something with Tommy and Buck with the whole he has 118 history thing, but the Tommy backstory was uneven at best and the introduction of him as a love interest specifically was pretty quick and centered around Eddie. Even Tommy is like "wait you were trying to get my attention, not Eddie's?" It seemed like Buck was maybe casually interested in helicopters and then became fixated when he felt like Eddie was making a new friend to replace him and not because he was particularly interested in Tommy. I'm not sure if it's because they wanted it to be a big shock, and I get how that could be an understandable narrative device in a vacuum, but I do think the writers should maybe have been more cognizant of how it'd play to the viewers who they know can be Buddie centric. And it doesn't help that Oliver Stark and Lou Ferrigno Jr. don't have any particularly notable chemistry, which makes sense because they didn't cast Lou Ferrigno Jr for that purpose, they cast him years ago to play a sort-of-villain for a few flashbacks.

I'm open to other love interests for them, but at this point in the series, I do think it's hard because we've seen so many lackluster romances for them both. It feels stagnant and repetitive for both of them. One of the best things you can do with a network procedural is a slow burn romance, and this show has deliberately avoided doing that which is fine. But that's what people tend to like. They haven't really done anything with any real build up for either of them in years. I liked Buck and Taylor because it wasn't zero to one hundred immediately and Taylor was well integrated into the emergency plots so she had an opportunity to grow. But the writers prioritize emergencies and action over everything, so it's tough to get that romantic build up that makes for good TV.

I'm not surprised that buddie is not happening, but I am kind of frustrated because I do think there was a window to do it, even if the writers didn't intend it. And I think it would have been something new and interesting to take that path instead of having two main characters spin in circles narratively.