From what I see, they are all skimping. Exchanges catching fire,...

From what I see, they are all skimping.
Exchanges catching fire, mobile towers using RF Backhaul. Lack of battery backup at mobile towers. No generators or small amount of diesel fuel available. Ageing inefficient air conditioning. Outsourcing to foreign companies to maintain the network.
The knowledge of contractors often is poor with relatively few people actually knowing how things work..
Ageing fire suppression systems..

As carriers move from 4G to 5G, IPv4 to IPv6 , move away from physical routers and equipment to SDN. Software Defined Networking. I don't think anybody will be immune from outages, in fact I think outages could happen more frequently as the technology moves to the next generation, before it settles down again...