I personally think the pension deficit might be a factor, a big problem for any company that offered pension schemes that predated the Blair government’s raid.
In theory it’s very hard for a company to shake of its liabilities to pensioners. In practice, selling off a part of the company, if the pension liabilities go with the sale, can help. The new owner can, if it helps, simply allow his company to go bust, at which point pensioners have to accept transfer to PPF with reduced income. The new owner meanwhile will have made himself a few bucks, while the original company continues to prosper.
All sympathies to BT pensioners but as pressure grows on BT to compete with other companies, that don’t have legacy pension deficits, I don’t see how they can survive.