3.5 is inherently imbalanced, but is that really an issue?

[MeimuHakurei]

Unfortunately, I'm unable to find it for quoting, but I remember vividly as some OP tell about how one player "overshadowing their whole party"
Herewith, the OP played as a Wizard, and the "gamebreaker" - as a single-class Fighter...

If you basically never use the Wizard abilities at any point and the game's challenges are something a decent party 5 levels lower could handle well, yes, the Fighter can feel like a game breaker. Especially if there's never any swarms, fliers, incorporeals, floating castles, underwater ruins, teleporting outsiders, enchantment spells, ability drain, undefined locations, stealth missions, intrigues, negotiations, harsh climates etc. in the entire campaign.