Nodes operated at a loss would depend upon charity and altruism in the community. I think it is reasonable to assume that nodes will only be run at a profit. But I think it is also correct to expect that routing will still be extremely cheap even if it is done at a price on the margin of satisfactory levels of profitability for node operators. Essentially you are just going to be paying somewhere between one and two hundred percent of the average cost of a node to a node operator divided by the number of transactions that he forwards. That should be minuscule. Something like 1/1,000th to 1/1,000,000th of the cost of operating a server.
To run what I consider a nice VPS is ~$60 per month.
So just to break even means for the VPS cost only, $60 /30 days = $2 per day
If I get
1000 transactions per day, meaning I have to charge $0.002 per transaction (30000 transactions per month)
100 transactions per day, meaning I have to charge $0.02 per transaction (3000 transactions per month)
10 transactions per day, meaning I have to charge $0.20 per transaction (300 transactions per month)
1 transaction per day , meaning I have to charge $2 per transaction (30 transactions per month)
1 transaction per every 5 days, meaning I have to charge $10 per transaction (6 transactions per month)
Looking at the above rates gives me a basis line for the competition of small hubs.
But let say I want to make a profit and am not working just to break even
To make a profit I charge based on the LN transaction volume , since small nodes can't go lower than breaking even
1000 transactions per day at $0.02 per transaction (30000 transactions per month)
100 transactions per day at $0.20 per transaction (3000 transactions per month)
10 transactions per day at $2 per transaction (300 transactions per month)
The above all give me $20 per day or $600 per month or $7200 per year
$7200 is not really a high enough wage to support a family, still below the poverty line.
so to make a living wage in California
1000 transactions per day at $0.20 per transaction (30000 transactions per month)
100 transactions per day at $2 per transaction (3000 transactions per month)
10 transactions per day at $20 per transaction (300 transactions per month)
The above all give me $200 per day or $6000 per month or $72000 per year
LN could support someone quite nicely , but only at $2 per transaction and if they can get ~3000 transactions every month.
So from the above the people working for free with small hubs will
break even charging between $0.02 & $2 per transaction.
While Large Hubs with 1000 transaction per day
can charge $0.20 per transactions and make a living for their owner.
Even considering 3rd world people running LN nodes and being happy with the $7200 only per year due to exchange rates.
It means that once the people get tired of just working for free,
that the bare minimum fees per LN transaction will be between $0.20 & $2 per hub.
Not the super low costs that were predicted, and still higher than many altcoins, including litecoin onchain which was ~2 to 5 cents per transaction last I looked.
Now a Mega Hub /Bank
that process 1 million transactions per day at $0.20 each transaction would earn their corporation $200000 per day or $6 Million Dollars per month
(Most channels & Users would centralize to this Mega Hub as to avoid additional fees further choking out the smaller players.)
If you can not see than LN was designed to be Banking 2.0 after reading the above, you were not paying attention to who can really profit from it at lower fees.
FYI: https://cryptoslate.com/bitcoin-lightning-capacity-rises-68-in-1-month-progress-in-scaling-and-micropayments/
the Bitcoin network has been settling less than 150,000 transactions per day.