But this network does not erradicate the costs of mining. Because of the high costs, miners will mine only for profit. For now, they can make profit with the coins that are generated, but with the "cost" of a continous "natural" bear market because coins are sold and drive the price down. So there is actually a high "hidden transaction cost" still not reflected in TX fees.
Yes , although the tx cost is being subsidized by speculators temporarily it simply is high because the 7tps limit and low tx volume. When the tx's start increasing multiple times over the cost of mining will be driven down substantially. Whether the price is brought down because the blocksize limit increasing, lightning network, interchannel payments, off the chain txs, or other solutions doesn't ultimately matter .