People who keep tracking their investments in USD instead of BTC are the dumb ones.
you are watching your favorite altcoin price in btc terms or in usd terms and why?
It is like a fiction price, because you invested that money on Bitcoin.
Just take a look at this:
You bought 1 ethereum at $300 (0.10 bitcoins when btc was $3000)
You sold 1 ethereum at $500 (0.05 bitcoins, because bitcoin was $10000)
In which situation you really would make a lot of profit?
Of course that in the "2"; if you just were a little bit more clever, you could hold that bitcoin and have right now $1000 because bitcoin doubled it's value.
It is just an example.