Birdstrike for what it's worth I agree with you and find that both sideslip and high AOA bleeds very little energy and makes dogfighting much less interesting because you don't have to manage energy loss very much. The lack of people on mulitplayer suggests many of us feel the same way.
Others will say "very little energy compared to what", and again I agree with you that the energy loss shouldn't be zero until you pull extreme AOA, it should register something.