But I want to ask if you already tried using Matic's POS Bridge, you can use the Low transaction?
For example, is the 23 gwei on the screenshot?
Not sure what happens when one use metamask (Metamask allows fee adjustment right before approving the transaction). But I have used walletconnect before.
I did try checking out via wallet connect today and was shocked to find out that despite ETH fees being low (20 gwei ~$1) the estimate for the deposit ~$5.4 via the bridge
Edit:
Metamask can let you edit the transaction fees to the lowest, but the problem is that the bridge uses a very high gas limit for Eth transactions - 94,491. As far as I know the normal gas limit for ETH (not ERC20 tokens) is 21,000
So fees could be even higher for ERC20 tokens.