Autonomous Senator Elizabeth Warren, known by many as an outspoken cryptocurrency skeptic in the United States authorities, criticized outages at exchanges and high transaction fees during periods of toll volatility.

In a Tuesday hearing of the Senate Commission on Cyberbanking, Housing, and Urban Diplomacy with Securities and Exchange Committee chair Gary Gensler, Warren claimed the crypto industry had fallen curt on providing solutions for financial inclusion in the United States. She mentioned the price drops amid cryptocurrencies, including Bitcoin (BTC) and Ether (ETH) last week, maxim "$400 billion in market place value disappeared" while many users reported problems accessing major exchanges like Coinbase.

Warren hinted that investing in decentralized finance, or DeFi, projects was "pretty risky" given the fact many accept not registered with the SEC and aren't necessarily inside its regulatory umbrella. In add-on, she highlighted some of the high transaction fees during periods of volatility — in this case, on Sept. 7, when the BTC price fell from $52,920 to an intraday depression of $42,843.

"The fee to swap between ii crypto tokens on the Ethereum network was more than than $500," said Warren, referring to trading a hypothetical token worth $100. "In the face of these loftier, unpredictable fees, small investors could easily get jammed and wiped out entirely."

She added:

"Advocates say crypto markets are all about financial inclusion, but the people who are well-nigh economically vulnerable are the ones who are most probable to have to withdraw their money the fastest when the market drops. [...] High, unpredictable fees can make crypto trading really dangerous for people who aren't rich."

Gensler addressed several questions from U.S. lawmakers during the two-hr hearing regarding a policy framework on cryptocurrencies, requiring companies to disembalm climate risks to investors, and other issues potentially affecting the SEC. In a prepared argument for his testimony released yesterday, he encouraged crypto projects to meet with SEC officials regarding securities the platforms may be offering in the course of digital assets.

Related: Sen. Elizabeth Warren calls crypto the 'new shadow bank'

Senator Warren has oft criticized cryptocurrencies as being tied to many illegal activities, including "unreliable tech," scams, and the industry's impact on climate change. Last month, she proposed banning U.S. banks from holding the reserves to back private stablecoins.