As things stand (25 responses), only 16% find it "exceptionally difficult" to communicate,
Without going into the statistical validity of this sample, I find your response astounding: only 16% find it "exceptionally difficult to communicate" with Tesla service???
Even 5% would be enough of a critical mass to permanently tarnish the image of a service based company. It's not that hard to pick up the phone or answer emails reliably and get back to people who spent $50,000+ of their money on Tesla products and on whom Tesla relies to spend more in the future.
Put differently: a 84% reliability score of the "bare minimum expected levels of customer service" doesn't even have a single nine in it ...
Fortunately Tesla is product based, not service based, for now. But as the Tesla fleet is aging service will be a more and more important part, especially due to the exclusive, single supplier nature of many Tesla repairs that makes owners dependent on Tesla.
But as @neroden said, the clock is ticking.