No long haul airline will touch regional flying. It carry's way more risk and substantially higher fixed costs in support and crewing for a lot less return. Those that do still have a regional setup its run as a loss maker to get pax to the long haul hub. Most I suspect would happily get rid of it these days but the short term cost of redundancy's etc make the accountants leave it until another day.
As you state though if the lack of connectivity hits the loads for the log haul network then they might consider doing something through a separate entity. I suspect though in the UK the additional traffic from regional airports would not warrant the expense. The reason why flybe is struggling is the lack of traffic and the competition of other forms of transport. Realistically quiet a few regional airports are uneconomic and routes out of them are thin and barely cost covering. If the punters are given a choice they will save 10 quid.