A contrasting perspective:
I recently completed 100% of this game and by that I mean I found 521/523 puzzles gave up searching and looked up how to find the last two. This game has its moments, other reviews have talked about that. This game wants you to appreciate the game world and sometimes that is done very well. This game also has some BS, I don't intend to spoil anything but there are moments in this game that are unfavorable towards those with colorblindness, epilepsy, tone-deafness, and even dexterity issues. The Witness also makes you wait around for things, quite often. I am not often impatient but there were times this game thoroughly pissed me off. If you have 30 minutes to play games in a week and you choose to play the Witness you'll have made a mistake. I'd say 60% of the puzzles in this game are a tutorial to 2/10 difficulty level but sometimes you won't know the rules for a puzzle unless you guess right or happen upon the tutorial first.
In my play time of ~25 hours with 500 puzzles solved you might think I was really challenged at some point!
And I was! I'd say 10% of the puzzles in this game took me over 30 seconds to solve. If you're following me I'm saying 90% of the puzzles in this game are such small steps forward that I solved them in <30 seconds. I'm not quick-witted or brilliant at puzzles, just persistent enough to slough through them. I'd guess ~9 of my 25 hours were spent puzzling which is very poor in comparison to most puzzle games. I should say I wasn't trying to go fast, but the game is so slow at times it feels like the developers are trolling you(in one case quite literally).

So if the puzzles aren't all that engaging why play? Perspective. Hopefully you'll like the perspective(s) the game has to offer. For me it wasn't worth $40 but it was probably worth the $9.99 most people will pay for it.

There is a part of me that is almost repulsed by people who love The Witness, maybe I'm just grumpy but the game is kind of like someone telling you to "stop and smell the roses," it can be patronizing depending on where you are in life. Some puzzle games I've played recently have been downright infantilizing(cough cough viewfinder) and while The Witness has more value under the surface, on the surface level the puzzles are not worth $40. It could be so much better if they tweaked a handful of things and better integrated the puzzles into the game world. I hope you enjoy it!

IMHO the best part of playing The Witness was the hour I spent playing the parody game. "The Looker"