Well of course the controller was the best part of the system, it was originally an add-on for the Gamecube. They just decided to instead rebrand and overclock the Gamecube to start over.
What it did was novel but it left a LOT of squandered potential. In order to catch the casual crowd they did not need to burn their core customers so badly. While there were (are) legitimately great uses of the wiimote, most of the time it came down to be an unwanted gimmick.
-Twilight Princess got delayed and gutted just so waggle could emulate a button press. We didn't get sword swinging as advertised in the initial Nintendo Revolution reveal trailer until a massive FIVE YEARS later, in a Zelda game most people aren't crazy about, that required yet another add-on, which required constant recalibrating. Meh, Nintendo.
-The obvious lightsaber game never got made.
-Where the hell is Duck Hunt?
-I didn't think Smash could get better than Melee, so all I expected from Brawl was shinier graphics and an online mode. Wrong, I didn't like the messy art direction, the online never worked and was a joke, and the game mechanics were all changed to make the game more Mario Kart random chance than skill-based fighter. I still hate this game.
-Sonic game where you need to unlock less shitty motion controls by playing the game with them intentionally gimped first.
I could go on, but the point is, Wii gave me almost nothing that I actually expected out of it. It gave me some other things I didn't know about walking in, however. Kind of like N64 when I expected a Yoshi's Island 2, but ended up with a Goldeneye.
So anyone who dislikes the controller or totally dismisses the Wii, basically if you have never played Resident Evil 4 Wii Edition, I can't respect your opinion. It's the definitive way to play RE4. It benefited from its last-gen design where you stop in one place when you lift the gun to aim -because your character can't move, you can use both the pointer and the stick to aim. Thus you don't have the "bounding box" clunkiness in other FPS type games. One could plausibly opine that a mouse/keyboard is better for an FPS game than a Wii Remote. However, the Wiimote+nunchuck is THE definitive way to play RE4. Everything else absolutely sucks in comparison. And it can only be done on Wii because they stupidly included an IR camera on Switch with no pointer option. The gyro won't cut it here, you need the Wii style solution.
When I played games like that, I wanted the industry to get moving so I could get that type of stuff but not running on a nonsense Gamecube. I was pretty sure we'd eventually get it, but we didn't.
So in short, the controller was a great idea, even if it needed an add-on to reach full potential. And while there are a few legitimately great uses of the Wiimote, most of the time it was just a headache that made more problems than solutions.
Crazy as this sounds, I think Wii's issues are more software related than hardware. The games that really used the thing to its strengths were too sparse.