There are 4 dungeons, 8 iirc with the dlc, that correspond to the main story. Besides the tutorial area, everything is optional; you can go right to the main boss. (I think speedrunners may have a glitch out of the tutorial now though)

There are a lot of puzzles, something like 160 shrines which give a 1/4 heart container (or stamina wheel piece) that each contain their own puzzle to complete our enemies to defeat. There are hidden koroks all over the world that give you an item when found that you can use to increase equipment carry capacity. There are NPCs all over that have some small problem and they reward you with money or cooking ingredients /etc. There's a variety of clothing hidden around and available from shops.

The story is, like most Zeldas, cryptic and expansive but told in a very kid oriented way. Skyward sword has the best fit for the tone imo.

Playstylewise I would say think of the original nes Zelda in the skyward sword engine minus the wiimote control. And add in durability mechanics on your weapons to encourage a variety of use

The focus is not so much puzzle dungeons with a boss at the end but exploration so you can figure out the story and get strong enough to comfortably kill Gannon.

The physics engine is very much this Zeldas gimmick, like how skyward sword has the wiimote controls or the ds games used the stylus. Many things are manipulable and can cause damage. The core combat however is very much the same as all 3d Zeldas.

The open world suffers from the Ubisoft problem of there is something slightly useful literally everywhere but it fortunately does not point this out for you with waypoints and stuff, meaning your clues are all environment based or clue based from NPCs.

The main dungeons are very similar to each other and not very difficult. Similarly the end boss is not super difficult.

The biggest reason I think people that don't like it on the first playthrough is the focus on exploration and just how long that can take. It's a big game

Second is the guys can be pretty beefy against weak weapons so combat can get tedious unless you try to do stuff with the environment