Bitcoin and the two Greyscale ETNs, GBTC and ETCG, are shortable here. Keep in mind the larger trend is up for bitcoin and ethereum (and ethereum classic which ETCG tracks). That said, the price of bitcoin is currently stretched, well beyond what is standard for on chain capital flows based on network value to transactions ratio (NVT). This was a classic short squeeze. Indeed, this last exponential mini-rise & mini-crash of bitcoin was NOT organic. The blockchain showed there were no major capital movements. The rise was orchestrated by big holders of bitcoin to milk profits via a short squeeze. That requires immense capital to buy up all the shorts. It’s done by institutions and whales.