Boggeds, unlike Strays (or Husks), do not replace a certain part of the skeleton spawn in selected biomes.
Strays and Husks replace the spawn of basic mobs at 80/20, but in the case of Bogged (which was intended to have 50% spawn) it is 50/100 for them and skeletons, instead of the expected 50/50, which means that we have a larger crowd of skeleton mobs in the swamps and generally more hostile mobs in swamps than in other biomes.