both are equally good for now because indeed they are a supporter of the exchange that is favored.
polkadot network designed to combine one blockchain network with another blockchain network. This is usually referred to as a multi-chain network.
uniswap a popular decentralized trading protocol, known for its role in facilitating the automated trading of decentralized finance (DeFi) tokens.
so it's natural that its use is very much done which actually pushes the price of the coin quite well. but on the way maybe polkadot will be able to survive well but maybe not with uniswap because obviously with decentralized platforms (DeFi) will experience problems compared to multi platforms.
but all of them will also give their best appearance by continuing to innovate as possible so that they can still be used and liked. everything on the way can change just whether they are ready and able to do that.
I do believe that there is a bit of a difference between them. Polkadot is a whole ecosystem worth of thing, whereas uniswap is a swap and that's about it. Both of them are in the defi world and that is why you may think that they are similar in nature but the differences is that there is a good chance you may end up with something much bigger with dot. I am not saying that it will happen, as long as there is community behind it and the developers do deliver then there could be a difference but if not then there won't be any.
So, the situation is this: uniswap has a promise and it is doing it awesomely and there is nothing wrong with that, on the other hand dot has something that has a lot more potential, if that potential is filled and they reach that, then that could be a lot better but if they do not reach that potential then it will drop very quickly.