The Chapter 11 was over four years ago, and was before NTL and Telewest merged, and then the take-over of Virgin Mobile and the re-branding.
That's like blaming BT for any problems O2 have now (even though they are owned by Telefonica) because in 2002 BT owned BT Cellnet.
btw, I agree with you re BT - I think there is enough competition now (but the Operators wanting LLU probably wouldn't agree).