Ever checked what the total crypto marketcap looks like when you strip out Bitcoin and Ethereum? It's a pretty wild metric to track. Those two mega-cap assets tend to dominate the narrative, but the real story is what's happening in the broader altcoin ecosystem. Altseason dynamics, layer-2 adoption, and emerging DeFi protocols are literally reshaping the landscape beneath the surface. Whether you're measuring pure market sentiment or hunting for undervalued plays, understanding altcoin dominance versus the Big Two is crucial for portfolio positioning.