Most coiners conveniently ignore block reward when calculating the cost of a transaction - that's your missing factor. Consider that the only reason you need to secure the blockchain is because it is mutable, if it were immutable it would be sufficient to simply publish it with a known hash. Ergo, 100% of the energy consumption of the Bitcoin network is attributable to transaction processing and therefore can be quantized into and proportionally assigned to transactions.

  TotalCost = DirectCost + ProportionalAllocationOfBlockReward

The value of the block reward is proportional to the price of bitcoin, and this block reward determines the ceiling of the consumption of resources in mining. The floor is determined by prisoners dilemma and so likely approaches the ceiling at the limit.

So yes, the transaction cost does scale with consumption of resources, albeit in a tail-wagging-the-dog kind of way, because the price of the block reward changes with price allowing more resources to be consumed.

Currently the actual cost of a Bitcoin transaction is $2.44 in direct costs + (6.25 * 41000)/2750 = $93 in indirect costs, so right around $95.44 - and that's using I believe the maximum possible transactions per block, the reality is it's more expensive still.

Move over Bank of America, there's a new king in town.