Nah, it's just that level adjustment is screwed up to begin with. If you
played an erinyes in an 18th-level group you'd be equally useless. And it means that an ogre PC is less able to take punishment than a halfling PC of the same level.
Basically, though they learned a little after a while, Wizards originally calculated LA by the level a spellcaster would have to be to recreate their strongest ability,
ignoring racial HD. Hence why the CR 6 nymph, who has casting as an lv7 druid but racial abilities weaker than one (their physical ability scores are lower than what wild shape can grant, and how often does a druid need high Int anyway?), has a +7 LA rather than +1.
Yes, this creates ludicrous situations where the ability to cast a 9th-level spell once per day costs +17 LA but increasing your Int costs +1 LA (which would give a high-level wizard the same effect via bonus spell slots
and make the spell stronger)
Pathfinder just uses CR instead of ECL for all purposes.
Races of War goes a little more in-depth for balance (starting with ECL = CR+1).
