For me it's not just about Tav not being central to the plot, it's that Tav isn't a character. I found roleplaying in BG3 to be the most disappointing experience I've ever had in a crpg and that is not hyperbole. Several games have done what BG3 have done in this area and done it far, far better. I also categorically disagree that Tav should have been voiced. I think that too much voiced dialogue in a crpg, especially for the main character, is a bad choice that makes the games worse. I want to be able to imagine my character saying lines specifically how I want them to be spoken. Not just that but voiced dialogue ends up limiting the scope for dialogue options and reactivity because then adding even an extra line to refer to a past choice costs exponentially more time and money. I understand that's a matter of taste, but having Tav not be voiced is one of the few choices I think was entirely correct from Larian.
