2 usd was in previous bullrun. At those time almost all coins and tokens cost in 10x or even 100x more than now. We should have another huge altcoins bullrun for siuch price
BTC was close to reaching $14k 2 days ago and we know that altcoins are also dependent on ETH and BTC so anything is possible. $1 also would be possible but now recently it dropped badly. It is not even listed on big exchanges which is why we can't see a good price of $0.5 too.