Modern pellets are basically the same design as they were around 100 years ago, just made more consistently and accurately on modern machinery. As a result of the design not changing they still have high drag giving low energy retention and poor wind behaviour and ballistic properties meaning that if the pellet and barrel are not a perfect match you get a shotgun group size.
Still, if shooters are happy to keep buying the same old stuff why should the manufacturers bother to change anything?