It seems that the argument is that although Hermione Granger and Ron Weasley are portrayed as the growing romance highlight of the Harry Potter series, they really shouldn’t end up together. The friendship between Hermione and Ron is fueled by the dangers of their world, which keep them united as friends, but this would not have happened without Harry’s involvement.
While Ron and Hermione have developed over time and work well as a team, their romantic relationship may have been a step too far for the duo. Ron may not be the most mature of love interests, and Hermione’s stubbornness can sometimes prevent her from seeing things from Ron’s perspective. Moreover, Ron and Hermione’s push-pull banter risks romanticizing stereotypes of dangerous relationships, which could be problematic for young readers who are still forming their perceptions of love and romance.
Overall, it seems that the argument is that Ron and Hermione’s friendship could have been a better representation of their dynamic, and that they may have been happier with other romantic partners. However, as with any work of fiction, the interpretation of the characters and their relationships is ultimately up to the individual reader.
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Ron is portrayed as a bully to Hermione in The Times

Although Ron can be an excellent friend to Harry and Hermione, he can also be a huge bully to Hermione. Ron is quick to want Hermione’s help in researching to help Hagrid with Buckbeak’s case, but in the same installment, Ron quickly turns against her regarding the Crookshanks and Scabbers. Plus, Ron doesn’t argue for Hermione when she brings Harry’s new broom to Professor McGonagall, though he would have known her intentions were good had he only listened. As a result, Ron and Harry ended up giving Hermione the silent treatment for a while.
When the Yule Ball arrives, Ron’s jealousy shows, and instead of being happy one of his best friends is having a good time, he is purposely bitter and mean to her, which ruins Hermione’s night. When Ron is humiliated and eventually starts dating Lavender, he imitates Hermione in front of everyone, which results in her leaving the room in tears. While donning a horcrux, Ron assumes that Hermione has chosen Harry over him, though at this point, nothing happened between Ron and Hermione anyway. This is not a simple and fun hassle. These are interactions that leave Hermione isolated and hurt by those she loves.
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No common interests

Ron and Hermione don’t have much in common. Ron comes from the Wizarding World, so he doesn’t understand Hermione’s background living in the Realm of the Spoiled. He is not interested in studying and argues against Hermione about her desire to help the House Elves. Meanwhile, Hermione is not enthusiastic about flying or Quidditch. What they have in common is loyalty and the many times they almost died. While Hermione is quite unique when it comes to loving studying, and Ron certainly has a wit of his own, they hardly get a chance to be intellectual together. Often, Hermione’s mind is fueled by Harry’s needs and plans. Rune strategy skills are used in other circumstances.
Although they didn’t need to have everything in common, they had enough differences to make them fight all the time. While they may agree on some things, others may lead to a powerful argument with lasting repercussions. For example, Ron didn’t need a love of studying, and Hermione didn’t need a love of Quidditch for their working relationship. However, they had quite a few differences to make sense of.
The Cursed Child suggests that Hermione would be nothing without him

Harry Potter and the cursed Child Hermione would have been depicted as someone with a successful career and a different love interest in the alternate timeline. Or, Hermione could have received a great career without feeling the need for a romantic partner. However, a choice is made to represent Hermione as a bitter professor at Hogwarts, who is suggested to be unhappy in any aspect of her life. The main thing different here is that Hermione didn’t end up with Ron. Why did Hermione’s marriage to Ron affect her career? In this timeline, most of the world still looks the same, as Harry defeated Voldemort. So why hasn’t Hermione had the same or similar professional success?
Harry Potter and the cursed Child He suggests an alternate reality where Ron married Padma, his Yule Ball date, and had a child with her. Although he doesn’t quite seem like the love of his life, he seems to be faring better than Hermione, whose life seemed to be on a downward spiral in the aftermath of the war, as she and Ron never met. This isn’t a good show of a healthy relationship, even if it’s an alternate universe meant to show how this version of the world is ultimately worse. Hermione’s relationship with Ron shouldn’t have such an impact on her career or outlook on life.