Is high reliability being neglected with modern technology?

I have IP telephony and two of three phone numbers are inactive. Error message says service under maintenance or overloaded. Since the main number is still active, it looks like they moved load onto fewer servers. Whatever went wrong, this shows that they don't apply the proper high reliability policy by providing proper redundancy (reserve capacity) and emergency strategies.
Further clue is that the service number automation didn't even put me on hold, but said I should call back later. Apparently they're flooded, too. Or, dunno, maybe overloaded, hah.

Before IP telephony, it never happened to me that telephone wasn't available. It was just always there.

I generally find it very bothersome that my provider sends telephone traffic over the regular internet connection and doesn't manage it separately.

Also recently the DSL connection broke down. It was kinda timed with their VDSL rollout, so I guess that messed something up. But you gotta realize that when the DSL connection (or even just the internet connection) breaks down, telephony does so, too.
And before IP, internet reconnect took a couple of seconds. Now, while there's no mandatory 24 hours disconnect (due to it being a problem with IP telephony using it), establishing it takes one minute and another minute for telephone to work again.


UPDATE: I now hear that my provider (Deutsche Telekom) experiences significant disruption of regular and mobile telephony in all of Germany. Allegedly they don't know what causes it yet. But come on, what?! Such a massive interruption and they don't know?


This is all symbolically interesting in light of how I got misled with deceptive information about VDSL availability. I could have had VDSL in August, but decided to get it from T-Online (complicated reasons), and now, contrary to all previous information, I learned they won't offer it for my household. So now I gotta go through a process of reverting back in order to negate a minimum contract duration (unless they manage a more elegant solution - hah, I don't think so) and then changing provider.


UPDATE 2:
Turns out a big customer had been switched in some way and they made a faulty IP routing entry somewhere, so a RADIUS server became unavailable.