Its not "un-economical". But it also isn't an argument. It is simply flipping the script on unit of account. Most people's unit of account is their national currency like the dollar. 1sat = 1sat is pushing back on measuring bitcoin against a moving currency like the dollar. Purchasing power is a better gauge. The dollar isn't a great thing to measure bitcoin against and due to the fact it is losing purchasing power over time its not really the best metric.

I feel ya though. Bitcoin's fixed inflation rate and the fact it has a cap is also part of the reason 1 BTC = 1 BTC isn't un-economical. Measuring your bitcoin in bitcoin terms is an important thing to consider. Not the short term fiat exchange rate. The exchange rate isn't useless. Its very useful but so many only think in fiat terms. Its like they only view BTC as a way to make fiat gains.

1 BTC = 1 BTC is just a shortcut. But, I suspect many don't get it and are just parroting a talking point.

My 2 sats.