yes... no sh*t sherlock, its very obvious that these prices arent sustainable.
Zcash current available supply is 767 ZEC! The supply will reach 100k during the slow mining phase before the full block reward will lead to a 7200zec supply increase per day.
At 20$ this would add 144.000$ value per day, so patience is the key, the 5-20$ range or below is where I start thinking about entering long zec. I expect 2-4 years of constant down pressure with rally (pump and dumps) in between.