To be fair, direct winter flights have always been unlikely.
Also, I won't be entirely surprised if some flights to Crete are cut back if my observations in the Apokoronas area are reflected elsewhere. For a number of summers, in Kalyves, there's been a gradual decline in the number of British voices heard around the village, in tavernas and on beaches. That trend in the village and its tavernas also seems to be affecting winter. I have no statistics but I'm aware that quite a few full time Crete residents have returned to the UK for various reasons.
There are now many more tourists (and new residents) from Russia, other eastern European countries and, particularly, Scandinavia. There are other pointers, too: most tavernas and cafés in the last two to three years have increased the numbers and sizes of menu boards in Russian and Scandinavian languages and recently English seems to be relegated to third place: ditto with menus.
I appreciate that Kalyves is a relatively small area, but popular, and if the trend here is reflected in other parts of the island inevitably there will be a decline in flights to match the number of visitors from the UK.
That having been said, there's no detail of what the various airlines are considering. They're in business to make profits and if particular destinations or routes are sufficiently profitable they're unlikely to be cut. Of course, a major influence will be which destinations the big tour operators decide to promote.