Is Uniswap illegal?

As a professional practitioner in the field of cryptocurrency and finance, I often encounter questions regarding the legality of various platforms and protocols. One such question that frequently arises is, "Is Uniswap illegal?" Uniswap, a decentralized exchange that operates on the Ethereum blockchain, allows users to trade ERC-20 tokens in a non-custodial manner. However, the legality of such platforms varies depending on the jurisdiction. So, the question begs: does Uniswap operate within the legal framework of various countries and regions? Or does it fall into a gray area, potentially subject to regulatory scrutiny? Clarifying these issues is crucial for investors, traders, and users of the platform. In your opinion, what are the key factors that determine the legality of Uniswap? And how does one ensure that they are compliant with local regulations while using such decentralized exchanges?