Comparison of gas fees between eth and bsc networks is very different, but users of the ETH network are still dominant and do not completely switch to other networks, currently gwei transactions are never stable and sometimes drop to 40 gwei so it is cheaper to pay for transactions on Uniswap.
Many are switching networks for their transactions. The good thing with many altcoins these days is that they're also supported in other networks. Like if there's an erc20 token, there's a chance that it's also in BSC for being bep20 token and as well as other networks that has lower fees.
That's why if you're sending that much in erc20 and you're too irritated with the fee. Always check the exchanges if they have support for that token in other networks for you to save much in fees.