Uniswap V3 is used in the initial version of Payment Abstraction to convert tokens into LINK due to its deep liquidity and decentralized integration capabilities

Quotes that support claims

On a periodic basis, the pool of fee tokens consolidated on the payment chain are converted to LINK using Chainlink Automation and an onchain DEX. The initial DEX used by Payment Abstraction is Uniswap V3, given its liquidity profile for supported tokens and the fact that it can be permissionlessly integrated by other smart contracts while minimizing centralized points of control. In the future, additional DEX services could be integrated to enhance MEV protection and support features such as smart order routing.