Why are miner fees so high on Uniswap?

Yes, the average gas fees for Uniswap trades are around $100 and can go as high as $300-400 based on the network gas fees. If you’re one who trades for less volume, you should try using centralized exchanges.3 Kas 2021

Once the gas limit has been reached, the miner will stop working on it. So, if your gas limit was more than needed, the funds would be returned to the operation generator. If the gas limit was too low, the operation will be canceled and the miner will keep a fee for their work .

Swap fees are not automatically reinvested as they were in previous versions of Uniswap. Instead, they are collected separately from the pool and must be manually redeemed when the owner wishes to collect their fees .