Context is important. Pretty much the entire aerospace industry is terrible at time estimates. SpaceX has accomplished some incredible things, so bashing them for "the whole Mars thing" when they are still hard at work on it seems premature and pithy.
And as far as I'm aware they never promised a 30k car? They promised a 35k car, which you can buy today (you just have to email them or go in person and ask for it, it's not available online)
He's always late with his estimates (aren't we all), but he sure is determined to deliver eventually.
I'm not always a huge Musk fan, but I don't understand this kind of criticism at all. Going to mars is something the human race hasn't done before, it's no surprise it is taking longer than expected.
And as far as I'm aware they never promised a 30k car? They promised a 35k car, which you can buy today (you just have to email them or go in person and ask for it, it's not available online)