how much the fees are going to be will depend on the level of adoption. it is more like a competitive market (similar to blockchain and how a transaction you send has a competitive fee). but the competition is no longer on block space since there is none in LN. the competition is with nodes, you can always choose a setting to go through a route that gives you the lowest fee. so if some nodes decide to ask for higher fees, they won't get to process any transactions.
I'm just putting a small warning out for the people who spread FUD and gaslight around. But I believe the fees will always be "low enough", but in times when the fees are not "unfairly cheap", fudsters don't say I didn't warn you. Hahaha.