In the case of an intermittent noise fault they cannot trace, they will bill you anyway, your fault or not.
Twaddle. I've had Openreach in my current house twice and never paid a penny. On the frst occasion the fault was undiagnosed, or they failed to inform me of the problem as it 'fixed itself'. On the second occasion it was a chipset incompatibility issue between a router and the exchange card.
They could have argued that it was my kit. They did not. Plusnet (and some on this site) were helpful throughout both occasions.
If BT are charging people for issues that are not the fault of the resident, then Ofcom need to hear about it. There may be isolated incidents, or ones where both parties refuse to accept responsibility. The fact that some of them might be elderly is neither here nor there. If there is concrete evidence that any company is targetting any section of society for unwarranted charges, the police should be notified.
You seem to have had a bad experience, but if I remember correctly, you complained about the package (60GB) before you signed up. You complained about the switch over, although it wasn't Plusnet's line at that point. You complained about their service notices, and they can be disabled. You complained about the tie in fees, although you must have read the small print.
Now you're away from them and you still complain. Please appreciate that I almost never (less than five posts in eight years) post in the Zen forum, despite leaving them for not caring for their pricing structure. It hasn't changed in the period since I left, nor will it, and I won't spend any time arguing about it.
While I do agree that some of Plusnet's systems are less than perfect, their general customer service (once you get the right people) is top notch, and their products on offer are as good as other ISPs (based on my experiences). Add in the fact that for me (opinions vary) the pricing packages are competitive, I can't complain unless there's an outage. Then I enquire, and if there's less than a satisfactory response, I complain. Once resolved, I've made my point, and that's that. No need to keep moaning if the problem has gone away. If the problems are semi-continuous, I would certainly consider an alternative provider, but only once I have established that:
a) My current provider can't / won't fix my problem;
b) Another provider can / will.