Sliding Scale for XP Loss

This might be the best of both worlds (remove or keep XP). Keep XP loss but once you get to lvl 90 or so then start logarithmically sliding the loss down based on the logarithmic increase to leveling. They could aim for a linear increase in time lost in XP that would realistically cap the amount of time lost at 2-3 hours of play time. For example, at lvl 90 you would lose the equivalent of 1 hour of time if you died and at lvl 99 you would lose the equivalent of 3 hours. This could maintain the difficulty of leveling and the reward while not disrespecting player time or builds.