This was also a gendered critique in many cases. Novels were considered fluff for women, that stuffed their heads with (supposed) nonsense. Which was likely a big factor in women writers sometimes taking male pseudonyms when they tried to publish. Women writing fluff for women . . . was adding insult to injury, in the minds of the conservative establishment, including the pedant class, which was pretty stuffy itself.
Trying to boil a complex thing down into soundbite form . . . It really wasn’t until the latter half of the 19th century — at least in the English speaking world — that these attitudes began to change. In cultures with a longer history of the novel, it happened much sooner than that.
Ironically, today, women dominate the field of the novel, and in my opinion — again, to generalize — produce the most great works. They innovate more. They go deeper. They take on social critique better, etc. Again, in general.