Calculate button on Swap to reduce friction =(max-gas)

Description:
When SWAPPING a token, the entire max value of the wallet, MetaMask will spit back the message ‘insufficient’ funds. And explain the gas value at something absurdly long in decimal places. This puts the onus on the user to pull out a calculator and do a subtraction. Why this inefficiency?

Purpose:
to remove the friction of calculating a value less gas fees

Extension/Mobile/Both:
both

Images/Attacments: