This service should be supported and used by Welsh travellers as it could be testing waters for a possible CWL-DXB in the near future.
The triumph of hope over experience...
Getting to CWL this way is VERY expensive, and much, much longer than doing it direct to BHX or LHR. As for the KLM, anyone doing this would not use EK, since KL can do the trip end to end twice daily, and at a lower fare, and with better baggage allowances.
I would be amazed if this option is used much. What you are seeing is EK adding to their network as part of an ongoing initiative to connect to airports they won't be serving directly any time soon.
And see my post above. It makes just no sense for EK to start this route, since it is bound to cannibalise yield elsewhere.
TA