Market observers are raising eyebrows at what some call 'irrational exuberance' flooding into U.S. equities right now. The sentiment? Too many retail and institutional players are loading up on American stocks with an almost reckless confidence.

We're seeing portfolio allocations skew heavily toward U.S. markets—way beyond historical norms. Some analysts argue this concentration risk is getting out of hand. When everyone's leaning the same direction, that's usually when the boat tips.

Sure, U.S. tech giants and traditional blue-chips have delivered. But is the party getting too crowded? Diversification used to be the golden rule. Now it feels like it's being tossed aside in favor of chasing returns in a single market.

Whether this ends in a soft landing or a harsh reality check remains to be seen. But one thing's clear: the risk-reward ratio is starting to look skewed.