Conflict is necessary for a story. That's a big reason why the "enemies to lovers" trope is very popular. The point where the "enemies" realize they have more in common than they thought is the basis for many books (as well as movies and TV shows).
There's something about the conflict that's exciting. We want to see the characters lower their guard and fall in love.
But stories can't just be the main characters fighting with each other. Or breaking up because they failed to have one conversation. After a while that's not going to be much fun to read about.
The problem might be that authors may not be sure what the real conflict is. Here's an example of what I mean. If your hero has been hurt and is afraid to be open, is that really a conflict? Sure, it can lead to conflict. But that isn't the one reason why the characters are in conflict with each other.
Instead of focusing on the hero's broken heart, how about going deeper? Maybe his issue isn't because the other relationship failed. Perhaps there were other factors that led to the failure. Maybe he had a loss of confidence due to other life experiences. If the hero's real conflict is within himself, his growth within the story can work for him. He can have the happy ending and fall in love again.
Of course, during this journey there will be conflict between him and his significant other. And that character will have their own growth as well. Both main characters will have to do the work to be ready to have the HEA or HFN that comes at the end of the story.
If the conflict is just the main characters making up to break up over relatively minor issues, it's may become boring. There should be more going on underneath - more conflict within the characters and more opportunities for them to grow.
When your story has romantic elements (but isn't a romance) you can make the same choices. Their relationship may not be the main event in a story like that, but it shouldn't be an afterthought.
The main characters may be in conflict because they're working together to solve a mystery or go on a quest. They'll have conflict and may even go their separate ways (temporarily). That's to be expected. But you can bring them back together to reach their shared goal while keeping the romantic conflict going.
For instance, in a mystery maybe your characters are chasing a criminal because they work together to solve crimes. They disagree over the next action to take and they split up. Conflict between them - and their methods - breaks them apart. Their romance would add another level of conflict for them.
They'll have to deal with it on both the personal level and the professional level. That can make for a very exciting story as emotional sparks fly while they pursue their quarry. In this case the conflict might be even better because they have to actively work through it, while reaching their shared goal.
The inner doubts and fears and the outer obstacles will force characters to grow. No matter the trope or the genre, conflicts are necessary and make a story worth reading.