I posted it just above you.
(Flash)
Lifelink's problem is that it's perceived as not being "cool" or "strong" enough on its own by R&D and gets thrown on cards as an ancillary ability when it has no business being there. (e.g. Griselbrand, Batterskull)
The problem with Hexproof is that ultimately it's just evasion*. It's really strong (in certain formats) atm because indirect removal isn't as prevalent and countermagic is weak. Thankfully, unlike Lifelink R&D seems to respect its power level appropriately enough, for now at least**. (sry krev)
It still should probably be phased out in favor of Shroud exclusively imo.
*pls no True-Name Nemesis pastarino
**pls no Geist of St. Traft cappuccino