I really do not complain about BTC transaction costs. I am a trader and I have many ways to avoid BTC trading but money can still come back to my wallet very quickly. For example, if you are trading on an exchange, you are holding 1 BTC. You can divide it and sell it at altcoins with low transaction fees like Nano, XRP, LTC, ETH, CS, ... then we can convert to 1 wallet and everything will become very simple. 
You call that simple?
You first sell your BTC for altcoins, you pay fees, you also have to set up wallets, and...you end up with shitcoins!!!
Most of us are concerned about sending BTC and receiving BTC not converting into some shitcoin.
What am I going to do if I want to send somebody some bitcoin, send them to an exchange...convert them to an altcoin, send the guy the altcoin then he sends to the exchange and converts them to BTC ...and he withdraws?
Paying twice the fees for BTC, twice conversion and withdraw fees?
Calling that simple!!!!!
I have the same feeling about all of this, and that's why I never bother exchanging my BTC to some fast alts in order to make a fast and cheap transaction. However, it would be interesting to see the real numbers. I bet you will lose more money in the process compared to just sending BTC and paying the highest reasonable transaction fee, like 40k+ sats currently, but it would be interesting to see the following calculations.
Say, someone buys $500 worth of ETH with his BTC. Sends ETH to wherever he wants. Exchanges ETH for BTC there. How much this person will really lose in the process? I assume, it can be more than $5, but I don't know how much exactly.