The US interest rates adjustment has always been absorbed by market forces like, FOMO ( FEAR OF MISSING OUT), Demands. However, Ether has not been performing well because the market movements is most times controlled by Bitcoin, that is, the Btc market dominance. Dominance is one of the weak link to altcoins even Ether token. As said, Ether underperformance is due to Bitcoin dominance, plus poor demands, and other market forces like speculations and hypes etc.