Is this a bug or something? or is it intended?

Is there a reason why the green Eldrid uncommon gear “Active Symbiosis Rune” gives Health Regeneration per Second while under 50% health but its purple Eldrid epic gear “Fortifying Symbiosis Rune” counterpart gives Maximum Health? is this a bugged gear like when the blue Rogue rare gear “Gambler’s “Boilermakers”” appeared as Epic rarity instead of Rare rarity? Anybody has any insight about this? it’s been like that for a really long time at least for me, maybe the devs have overlooked this?