> According to cryptofees.net, BTC transaction fees average 4%

That site hasn't been updated in almost a year. (Check the prices and recent transactions it links to.)

Here's a more accurate way to estimate bitcoin's fees. Go to mempool.space and look at the current estimated Low/Medium/High priority fees. That is based on current pending transactions and most of the time, unless you are in a hurry, "Low" is enough to get a transaction confirmed in the next hour.

At current writing, and for most of the past year, those fees are a few cents.

And this is the expensive way to transact bitcoin -- on-chain! Nowadays most commerce is moving to the layer-2 Lightning Network, where transactions are instant and typically nearly free via payment channels that are settled on-chain in the future.