The cost of a bitcoin transaction is not adequately captured by transaction fees. There's two alternative ways to look at it:

1. Divide miner revenue (fees + seignorage) by the number of transactions, yielding the total amount that miners extract. It was $34m today, with ~261k transactions, yielding a cost per transaction of $130. [1]

2. Estimate energy cost at 1,173 kWh per transaction [2]. If you assume cheap electricity at say $.09/kWh you get a cost of $105 per transaction in electricity alone, which ignores hardware capital costs, etc.

Either way the cost is over $100 per transaction, and would be reflected in a falling value of BTC. But it may be masked if there's an influx of new money into the system.

1: https://ycharts.com/indicators/bitcoin_miners_revenue_per_da...

2: https://fortune.com/2021/10/26/bitcoin-electricity-consumpti...