You’re missing out! I’m not a fan of the cheap Bordeaux white plonk, especially when dominated by or entirely Sauvignon Blanc based. The blends with a heavy Semillon influence are very different and can age very well.
The blends produced by some of the sweet wine producing Chateaux and wines of Pessac Leognan are particularly worth trying. The fuller richer blends really lose the astringent nature of Sauvignon blanc which I dont like.
I think bordeaux white wine is similar to riesling in often being an unloved white wine. Show it some love.