Bitcoin (BTC-USD) weakens again, dropping 10% in the last 24 hours, to ~$35.8K, continuing to retreat from its almost $65K peak in mid-April.Over a week ago, bitcoin came under pressure as regulators, particularly in China, cracked down on the world's largest crypto and critics and supporters debated over miners' energy usage and its impact on the environment.Last night, high-profile investor Cathie Wood came to bitcoin's defense at the Coindesk's Consensus 2021 conference.The crypto is "already on its way and it'll be impossible to shut it down," she said, while predicting that regulators "will be a little more friendly over time" toward cryptocurrencies.Other cryptos are also sliding — Ethereum (ETH-USD) slumps 12% to $2,482.88, Litecoin drops 28% to $171.88, meme crypto dogecoin, dips 11% to 31 cents, and Cardano (ADA-USD) falls 14% to $1.50.Bitcoin-related and crypto-related stocks dropping in premarket action include Riot Blockchain (RIOT) -5.5%, Marathon Digital (MARA) -5.3%, Bit Digital (BTBT),