It had catchy songs (One of which is one of the best ballads in the series, in my opinion), a very valuable moral, a kind of "thinking-outside-of-the-box" mentality, and some funny characters. It had good reasoning as to why Littlefoot wanted to help the Yellowbellies, and it was very relatable.
I actually love the yellowbellies. I was laughing pretty hard at some of the jokes. They got good actors to play bad characters and, you know what, it did pay off. The characters learned something, had an adventure, got home safely, and that's really what matters at the end of the day. It's not spectacular by any means, but I think that if you go into it with the mentality of "You know what, this is in no way going to stand up to the first one and it's going to be terrible so I'm just going to take it for what it is," then you won't be disappointed. It's actually really cute. If someone came up to me and said, "Hey, buddy, want to watch Land Before Time 13?" I would say, "Sure! Crank out the popcorn, friend!"