Energy Consumption and Environmental Concerns: Some blockchain networks, especially those using proof-of-work consensus mechanisms, require substantial computational resources and energy consumption, raising concerns about environmental sustainability.

Legal and Regulatory Uncertainty: The unclear and fragmented legal and regulatory environment surrounding blockchain and cryptocurrencies poses risks and uncertainties for businesses and individuals, limiting their investment and development in the space. 

I'm so grateful for the knowledge you've shared! Ngạc nhiên quá! 😘  @meobu