you're not going to punish tanya teleport from a jip because the frame data always change depending on how high you are. only one char can do it 100% of the time for free is cassie.
Then explain the me how this is a gimmick if people aren't actively punishing your other options.
Let's take snake eyez from street fighter for example. A strategy he is famous for is whiffing sweep and then command grabbing the button his opponent tries to whiff punish with. There are few people who are able to active whiff punish sweep, and with those people he would use crouching light kick directly into EX command grab (which is invincible).
This strategy is for people who DONT ACTIVELY punish teleport, and for the ones who do, Tanya is still able to cancel into EX rekka for the armor upon landing.
It's not useless, nor do I believe it's a gimmick.
Example:
Tanya does f2 canceled into back teleport, the opponent attempts running in to either punish or evoke pressure. Upon landing Tanya does ex rekka and punishes the run in.
The next time, the opponent expects the EX rekka and blocks out of respect. Tanya cancels landing into grab, successfully grabbing the opponent.
If this is truely a gimmick and won't work against people who can defend against it... Then everything in this game is a gimmick.