Ripple has launched RLUSD, a stablecoin, which could challenge existing market leaders.Stablecoin liquidity has reached a record high of $169 billion, indicating increased confidence in digital assets.Tether (USDT) and Circle (USDC) dominate over 90% of the stablecoin market cap.The entry of Ripple's RLUSD token and regulatory changes pose a potential disruption to the stablecoin market hierarchy.