3D World is totally different in my oppinion. Odyssey, like most 3D Marios, is more exploration, puzzlesolving and adventure. 3D World (and 3D Land) is effectively a 3D platformer.
While i really enjoyed Odyssey and think it had some of the best ideas in a 3D MArio in a very long time it often felt to easy, if not simple. Sure, getting all 999 moons might be challenging, but i would've preferred more overall challenge and less collecting madness.

Blasphemy!  DK Tropical Freeze is by far the best platformer on the Wii U.
Now that its getting ported to the Switch, it wont be forgotten for along while.

Ehhh, maybe top 10 platformers. It's not top 5 - definitely below Super Mario 3D World, Shovel Knight, Trine 2,  Rayman Legends, Super Mario Maker, Shantae: Risky's Revenge, and Axiom Verge. 

And the Switch port announcement didn't raise a lot of excitement.

Yes I had way more fun with 3d world than Odyssey

Breath of the Wild>>>>>>>>>Oddyssey>>>Mario 64>>>>>>3D World

Galaxy 2 > Odyssey > Galaxy > 3D World

Galaxy 2 had some of the best levels ever in a 3D Mario game and refined every mechanic of the original galaxy. The addition of Yoshi was great, the soundtrack was great, and I could replay this game over and over again without getting tired of it.

Odyssey is an amazing game but the power moon mechanic eliminates a lot of the challenge that I enjoyed from the Galaxy games. A lot of the power moons are just sitting out in the open, waiting to be picked up, while others are simply hidden behind a wall that just requires a simple double check to find. I love the game and each of the kingdoms as well as the numerous ways that you can traverse them using jumps and the cappy mechanic. but without the challenge i have no desire to play through it a second time.

Galaxy was a great game but simply falls into the shadow of Galaxy 2.

i hated 3D World with a passion. the camera angles made the game difficult to move through, and being made for multiplayer, i feel like a lot of the level designs were limited and shallow.

Interesting. I've only read through the first page of this thread, but I can see that some people agree with the OP about Odyssey not meeting the standards set by the previous games. My younger brother played Sunshine but didn't beat it, then he beat Galaxy 100%, played lots of 3D Land and a little of 3D World, and now that he's playing Odyssey, he says it's the best and really beat his expectations. Though I suspect a large part of that is because of the music scene in New Donk City. He had not gotten wind of it from trailers or anything before playing the game, so it blew him away.

I didn't play 64 when it first came out, and all my attempts to get into it later didn't go well (Mario 64 DS....bad controls). Didn't play Sunshine. Galaxy completely blew me away and became my 3rd fav game of all time. I'm currently still playing Galaxy 2, which feels like continuing Galaxy 1 to me. I'm almost 100% through 3D Land, and I enjoyed it more than 3D world, but maybe because I've only played the first few worlds of 3D World in co-op. Never in single player. That said, I'm only about 7 worlds into Odyssey, and I'd put it right behind the Galaxy games. Remember, I never played 64

I think 3d world has more to offer as the better multi player game, and in my opinion was more enjoyable.

3DWorld is a fantastic game, one of my favourite games last gen. I still don't think that it's comparable to SMO, because they're actually pretty different games.

3D World is a great game, but it lacks the ambition and scale of the other 3D Mario games (64, Sunshine, Galaxy 1 & 2, Odyssey). Also, the larger exploration-based levels of the others puts them way ahead of 3D World, in my opinion. I personally think Odyssey is my favorite of all the 3D Mario games. Galaxy 1 & 2 were tied for being my fave up until I played Odyssey. 

Another opinion: I liked Odyssey more than BotW, although the latter's still a fantastic game :)