Definitely have harped on this A LOT already, but since that post is still getting some notes.
One of the number one things that makes the message of the hmc film so inferior to the book is that Sophie considers herself ugly/plain. And how Howl reacts to her appearance.
Sophie in the book is pretty and she knows it. This is a BURDEN for her, because she feels the eyes on her. Men scare her. People judge what she does. When she becomes old, she is now beneath notice, and this frees her to act however she wants, and it frees her from worrying about the attentions of men. But the thing is—it turns out she is not beneath notice. Howl falls in love with her despite being an old woman. He does know she’s actually young, and he does wonder about what she might look like, but he very clearly falls in love with her while she is an OLD woman and he has no idea what she might look like (besides a guess).
In the film, she believes herself plain. Instead of it being about anxiety and the male gaze (things many women can relate to) it instead becomes about... body image. Many women can also relate to this, but it feels like very low hanging fruit for a story a man writes about a woman. Ah, it’s about a woman, so she must consider herself ugly, so the romantic attention of a man will Fix That Right Up. It’s like that One Direction song. You might even say that Sophie is longing for some male gaze. On TOP of that, we see that Howl remarks that she’s beautiful when she turns back to her young self, and recoils when she goes back to being old. Not encouraging.
Overall the film feels like the kind of story a man would think a woman would relate to, while the book is a story clearly written by a woman for women. In the film, the attention of a man fixes things (or at least is generally a pleasant interaction). In the book, the attention of a man (and her own romantic feelings) REMAIN something uncomfortable and difficult for her. That is a much bolder choice, imo.