What is this rant actually about?
Are you complaining about the fact that there are still landlines? You might consider them legacy, but they are also a part of the universal service obligation from Land's End beyond John O'Groats to Orkney and Shetland. Personally, this is something I think is important.
I would expect that a huge proportion of Reg readers have taken advantage of Local Loop Unbundling (LLU) to get their broadband service from someone other than BT, but how many of you have done the same with your phone service?
Why do those who stick with the incumbent expect things to change for better for them?
Despite the fact that telecommunications were privatised much later in Germany than in the UK the system seems to be working better. LLU was introduced shortly before 2000 and I immediately took advantage of it and haven't looked back. There are many accounts that LLU, introduced even later, in France and has been a success, even prompting the notoriously slow and surly France Telecom to up its game.
I think that what you're really describing is a failure of regulation both to encourage competition and to maintain standards. From the very start privatisation of the phone service (and later other utilities) in the UK was flawed. Cable & Wireless (itself a product of privatisation) was not allowed to compete with British Telecom for the same services and so mainly concentrated on companies. The carve up led years of record profits and combined with underinvestment. When LLU was introduced it didn't come with enough incentives for other companies to invest either. This is why the situation in the UK is the way it is.
Some other points:
paying by direct debit
This is pretty much every contract even though it actually costs the providers money – banks often charge to hold the money in escrow because it can be clawed back by an account holder. If it can't be excluded by the contract, then the provider will seek to make alternatives as expensive as legally possible. The costs associated with potential non-payment are simply too high. An alternative, of course, might be to introduce PAYG for landline. Remember when they did that for the leccy?
This really is up to the regulator to enforce as part of the service (it's in the spec) to prevent the Ryanair prices you describe. Companies wanting to avoid showing direct lines should should show the number of the switchboard.
Again, this is really down to the regulator. I've only ever had a few in Germany but have always complained (caller id helps here) but since the fines were significantly increased a couple of years ago, I believe that particular problem has largely disappeared. When it has happened, I never got angry I just told the caller I would be lodging a complaint and noted the number. It probably helps that the provider of connectivity for the nuisance caller can be held responsible, so that even if the number is withheld the phone company can track them down using their logs.
has been available here for years, but as others have pointed out, it's not really any cheaper to run
When it comes to switching providers, price should never be the only reason, though it may be the most important one. Other factors such as minimum length of contract and quality of service matter as well. VoIP is cheaper than POTS, Since I made the switch in 2006 I've had more than enough dropped calls or calls with too much interference to gloss over the problems and a VoIP connection requires an individual power supply. The agreed service level in the contract is only 99 % which is one of the reasons why it's cheaper. Nevertheless, network-based VoIP for all new contracts is now standard in Germany.
The costs should also be given some historical context. I'll bitch as much as the next man about the telcos but costs both in nominal and real terms have come down significantly since the 1990s. I used to pay around DM 0.80 a minute for calls back to the UK. A flatrate for calls within Germany has been standard here since about 2005 and I've had a flatrate for calls (to landlines) for Europe and North America for about the same period.
Officially I've still got ISDN, though it's run through the FritzBox and doesn't get everything right, notably forwarding the number of a caller when I redirect a call to my mobile. I guess I should start investigating how I can replace the setup (hardware and config) with straight VoIP.