Dave Filoni sticking his OC absolutely everywhere is obnoxious, especially when it goes so far from where her character has any right to be.
She has the right to be wherever she wants to be.
Sorry to break it to you, but Ahsoka isn’t real. Dave Filoni is real, however, and he seems intent on shoehorning Ahsoka into every project he works on. I get that he feels proud of creating such a popular character, but putting her everywhere and making it so that she can never die causes her to overstay her welcome somewhat.
People make this argument about ‘narcissistic Dave Filoni sticking his cartoon characters in everything he does’ all the time, and I still find it unfair. Ahsoka was already a main character of The Clone Wars, she basically guest appeared in Rebels, and she’s the perfect choice for a Jedi for Din to meet in The Mandalorian. If you had created a character you liked, you knew interesting ways to expand their story, and there was great popular demand for the character to appear in more content… would you really resist doing it, in order to appear less obnoxious?
I know that she’ll probably appear in The Bad Batch series as well, and that’ll probably drive some dubious fans such as yourself over the edge, but I personally love Ahsoka and I’ve never seen a proper reason to not include her in something. Besides, The Bad Batch looks like it might end up a bit of a dull show if Ahsoka and Rex aren’t in it.