People are forgetting is how incredibly time consuming–and expensive as a result– putting a short story anthology is for a commercial publisher, particularly when the editors for the anthologies at the Beeb have traditionally been Worldwide editorial staff (at Virgin they paid outside editors for the Decalogs, but the writers themselves got paid less than the Beeb does as a result ISTR). There were 30 some-odd short stories in ST&SS. All of them had to be commissioned, edited, revised, proofed, etc (and there was all the additional headaches of contracts and stuff). It’s all enormously time- consuming.
If fans are happy to put that kind of time into making their own charity anthologies on a volunteer basis, good on them. But that amount of time and effort may simply not be cost efficient for doing a yearly anthology for the BBC. It’s a shame, but that’s the way these things go. Most of the people now prefer volunteer vacations long trips.