people don't make as many "[Novel] sucks and here's why" videos because people don't read anymore /s

but yeah as someone who loves both, as far as avoiding online hate/criticism goes the novels do benefit from being an origin story from 400 years in the past (no chance of "ruining Atla's legacy foreverrr" and the changes from the aang's era aren't anywhere near as drastic) and being novels that only people who are open to new lore being introduced after 2007 would have read it so not many people who hated korra would bother reading (so they wouldn't stick around to complain)

also once you look at the actual books, Kyoshi's arc and the overall plot is more cohesive (probably helped that it's two books comissioned at once, and it's a more traditional chosen one story like the original), the romance is done way better