Just reread your post...
You are basically arguing semantics at this point. Why does a wood elf get to hide in light concealment? I say because they are harder to see.
I'm arguing rules not semantics. The Elf ability does
nothing to remove the restriction that you can only hide when you are 'not able to be seen clearly enough' - it only allows the Elf (when unable to be seen clearly enough) to hide in light natural obscurement once that condition is met (something an Orc or Human cannot do - those races have to first 'not be seen clearly enough' and THEN they need to find cover or total obscurement).
Despite a creature not being able to see you clearly enough at the start of your turn (it may have its back to you, or be distracted on account of a swirling combat) and thus you meeting the first condition of making a stealth check to Hide, you may not be able to meet the second condition of making a Hide check - reaching appropriate cover or concealment to hide 'in'... all while remaining unobserved in the process.
A Human who starts his turn 'unable to be seen clearly enough' and thus able to Hide still needs to reach appropriate cover or concealment to attempt the check. He might not have any cover or total obscurement to hide in within his movement distance. Or in order to reach that cover or concealment, he might have to run across the open ground or in front of the creature, thus blowing his position (and denying him the ability to hide) before he gets the chance to make the check.
The Elf doesnt have this problem. Any natural obscurement will do. A ficus, pouring rain, mist, long grass etc.
Practically speaking, the ability enables the Elf to Hide far more often than a Human or Orc will be able to.
And personally I don't view the ability as making the Elf harder to see
when not hiding at all. If the ability was supposed to represent the Elf being harder to see, then it would say so. An Elf is just as easy to see as an Orc when the two aren't trying to Hide. The ability just makes the Elf better at not being seen when he actively tries not to be seen, and is in appropriate natural terrain, and isnt under direct observation.
An Elf cant walk behind a ficus in full view and gain total obscurement or attempt a stealth check to Hide. He is as easy to spot behind the plant as a Dwarf who followed him behind a ficus.
What the Elf can do is (when no-one is can see him move behind the ficus clearly enough) use his supernatural inherent ability to attempt to hide behind a ficus. No matter how good the Dwarf is (barring the Dwarf picking up the Skulker feat) he will need to reach a wall, hole or other total concealment or cover to hide in.
I personally rule that one needs more than just light obscurement to satisfy the 'cant be seen clearly enough' requirement to be able to make a stealth check to Hide. If all it took was light obscurement, then the rules would just say so (Something like: You can attempt a stealth check to Hide any time you have light obscurement or partial cover relative to the creature you wish to hide from). Instead it leaves it up to the DM to determine when you cant be seen 'clearly enough'. For mine, this implies more than just light concealment. The creature needs to be distracted as well, focusing on something else, or be looking the other way.