The Simpsons characters, from a job/occupation POV, never really changed after all these years.
So what's happening basically is that the 'funny' stereotype from the 90s sticked and became a model of mockery towards those ill willed towards individual native from India.
I get the point offended people want to get across, but honestly, even if Apu changes or even disappear, the show is now 29 season long and the stereotype/joke won't disappear like that.
Simpsons (especially back then) did a lot of its humor through caricature and personally, if some douchebag is willing to piss Hindu folks with jokes like that (à la douchebags in the first Harold & Kumar), that's on them for being fucking racists.
I mean, even if the Simpsons were not a thing, racists would just find other material. Not dismissing the issue, criticisms are valid but imo, this is a case were the bad done by this is done and well implemented, like, you can't turn back, it's useless. I don't think Matt has ill intents by saying this.