If you want incentives, run a public LN node, be a LSP.

That's probably the strongest argument against protocol-level node rewards.

Lightning routing, LSPs and other higher-layer services create market-based incentives without changing the base layer.

The question I'm wrestling with is whether there is any infrastructure that benefits the network as a whole but doesn't have a natural market attached to it.

If every useful node service can be monetized voluntarily through higher layers, then protocol incentives may be unnecessary.

If not, there may be a case for experimenting with them.

I'm genuinely not sure where the line is.