But payment channels, and their capacity, are actually limited by how much Bitcoin the people who run nodes hold, are limited by how much capital they want to open payment channels with, are limited with their technical-skills in how to maintain the node/balance channels.
And if they are a smaller public node, like one of mine. If they have a need for the
BTC someplace else.
I just moved all the funds out of one of nodes because I was to tired to deal with moving some funds out of cold storage.
It's part of the reason why commercial businesses are critical here IMO. They have a plan, they put the funds in and leave them there and keep them balanced.
Unlike Dave who puts them in and plays around and then pulls them to get a new laptop because the charging port on this one is wonky and going to fail sooner or later.
-Dave
That's it! That's the point! Because if the capital "invested" in LN payment channels could earn you profit, enough to make it have a feasible rate of "investment", then the more sensible thing to do is, leave the "investment" alone and look for another way to buy the new laptop.
Capital is limited. I believe the altruism that boot-strapped LN would be replaced by participants based on incentives.