More like, you either don't know how to play, or they're just not fun to you personally.

Tekken is much less popular nowadays than in the late 90s early 00s.
Basically, the roster is huge, and the movesets are huge too, so complicated that almost no new people become fans of the game because of how much there is too learn, and also, since it is a tekken tag game, it makes things worse, since you should be able to dominate 2 characters in order to be able to play decently.

Tekken 6 will have a smaller roster, Namco recognizes that as a problem.
The game is great, but very niche. I have always prefered Virtua Fighter btw.

The only multiplatform the Wii U didn't get that I would have bought this year is Ultra Street Fighter 4.

I bought it for $9. Does that count?

Yup.  However, most people will enjoy Tekken over Virtua Fighter because Virtua Fighter is even more complicated than Tekken, while not being as flashy, or visually appealing.  Combos are a lot more character specific in Virtua Fighter, while in Tekken, generally speaking, combos you learn will apply to most, if not all of the entire cast.

Finally, it's a lot more bare.  We've know Jackie Bryant, Wolf, Kage, Vanessa, etc. for many years, yet there's not much of a story?  Kage's mother is Dural, and Vanessa is/was Sarah's body guard and was going to be the next Dural because of reasons?  And, in virtua fighter, weapons are not allowed because of tournament regulation, or something like that.

The character's aren't much.  It's not flashy, and that voice acting...  Wolf gave me a chuckle in VF4, though...  His lines were gold.

But, Tekken get all that stuff right.  It has good voice acting.  The game is flashy, but not fireworks-happy like Marvel Vs. Capcom 3 is.  The characters have interactions and stories expressed in the game and it gets more than 2 characters per sequel.

However, Tekken's character problem is because of the team trying to make each game bigger and bigger.

Their eyes are open now.  What was once joked about, like a devil ganryu will never see the light of day, because....  No body likes Ganryu.  They kept re-using characters, bringing them back over and over, when a majority of the characters don't get used or are liked.  I've faught Ganryu once, or twice....  About a year ago.

I'm glad to see the cast go... Probably because with the announcement of Tekken 7, all my mains that I used prior to Tekken Tag 2 had been announced.  Leo, Lili, Feng Wei...  All in Tekken 7.  Oddly enough, the one character I picked up in Tekken Tag 2, Yoshimitsu, because I figured that being in every Tekken game, (revolution doesn't count) would mean he would be in Tekken 7.  But, he hasn't been announced yet.

I hope to see him.  I hope the tweet from a while back was just a troll tweet on Harada's behalf, but there's a chance he wont come back.  I hated how radically different Kunimitsu was from Yoshimitsu in Tekken Tag 2.  I thought it was great that a clone character could be so different and wouldn't mind seeing her in Tekken 7, but I personally will not be using her at all.

Before I drift too far off, I just wanted to say that you were spot on.  But, eventhough there are a lot more attacks in newer Tekken games, I hope they skim off the useless ones, and not just get rid of random moves just to shorten a list.  Every character in Tekken has moves in their list that are absolutely useless.

The only character who benefited from useless moves, or rather, extremely situational moves, was Yoshimitsu.  He has something for every situation, and his randomness, when done properly can be extremely dangerous.  But some characters have moves that are outclassed by other attacks in the move list..

You can do attack A, or attack B, but attack B works in the same situations as attack A, while also dealing more damage, giving you fewer recovery frames, etc...  So, if you do attack A, you are a fool, or a troll.

Tagging, and large character rosters needs to be a trait of Tekken Tag Tournament games.  It should remain to be that Tekken game that tries to please everyone.

The novelty of having almost all the characters in the game has worn off considerably, simply because Tekken 5 brought back all those old characters into the game, and again with 6.  Getting a breath of air, and fewer characters would be good, and giving a break from all that will help out when Tekken Tag Tournament 3 comes along with the 70 or so characters it will probably have.

Also, another thing.. Character default costumes.  Personally, I'm sick of looking at all the stills, cards, and whatever else, with the characters wearing the same outfits from Tekken 5.  It makes the game look... stale, and a little old.  Sure, you can change character costumes, but that only works in the actual fight itself.  Pre and post fight, all you see are the same costumes for everything pre-rendered.

That's one reason I think Yoshimitsu hasn't been shown yet.  I think they are changing default costumes for Tekken 7 this time around..

TL;DR:

Tekken does have too many characters, there are too many moves, and it's too much for a single person to take on along with game mechanics.  Like Rage, bound, parries, grab, counters, chicken reversals etc. and etc.  

The Wii U version suffered because most Tekken players aren't playing on Wii U and had the game well before the Wii U version was released.

It's problems are probably going to be fixed with Tekken 7, but Tekken 7 will be exclusive to Xbox One, PS4, and PC.... if you can call that exclusive.  And, while it isn't perfect, it doesn't have the same problem Virtua Fighter has.

I've never even heard of this game.

I actually own Tag Tournamnt 2 for the WiiU and I like it! For a spin-off it's very good!

I bought it few weeks after launch.

Great game, excellent multiplayer, since you can use every Nintendo joystick (Wiimote, Nunchuck, Pro, Gamepad). Gorgeous visuals and music. It has two extra modes that are not available on other versions.
Online works just fine.

I also don´t understand why early WiiU adopters did not got this game.... maybe Nintendo audiences don´t care much about fighting games.

And also for the 3DS !

yep, i bought it for $25 AUD - pretty good for that price.

The costumes are hilarious =D LOL @ the princess peach one

Great game. Highly recommended.
I bought it for PS3 because that version was already discounted when the Wii U version was released.