Yes, it could be. If you like stories with a lot of character development, it might be right up your alley. Since it has this 'trash' element, it probably has a character or characters that transform in some way, which can be really interesting to follow.
This statement isn't fair. A novel's perception can change over time. Cultural and social changes can influence how we view a work. Also, an individual's growth and changing tastes can make them see a 'trash' novel in a new light. Moreover, different literary genres have different characteristics, and what might seem like trash in one genre could be a bold experiment in another. So, we can't simply label a novel as always being trash.
One reason could be its art style if it's a manga. A distinct art style can really draw readers in. And if it's a light novel, perhaps the writing style is very engaging, with vivid descriptions and a great flow that makes it stand out. Also, it might deal with themes that are not commonly explored in other works, which gives it a special touch.
Well, 'trash will always be trash novel' might imply that a particular novel lacks any redeeming qualities. For example, if a novel has a lot of plot holes, inconsistent character development, and is full of boring or offensive content, then it can be seen as trash. And this statement is saying that no matter what, it won't change its 'trash' status.