The decrease in mining revenue indicates a potential reduction in profitability for Argo Blockchain, which is a critical factor for investors. Additionally, the sale of a significant asset such as the Mirabel, Quebec Data Center could be viewed as a strategic move to raise capital or reduce operational costs, but it also raises questions about the company's future growth strategy and asset valuation. These factors combined have likely contributed to the negative sentiment among investors, leading to a decrease in the stock price.