Something being less subject to defaults in practice is not equivalent to a system in which defaults are not possible.

Lightning is lightning, it isn't anything else; trying to reason about word pattern matching obfuscates understanding rather than enlightens. If what someone disliked about a weeblix system was that it subjected users to flimdar, then it would be pretty misleading to suggest people wouldn't want some feature that made a system more weeblix like if it didn't expose them at all to flimdar, even if it was otherwise weeblix like.   In this case, I don't even think it's fair to say that lightning is "like" netting, as all transactions in it are ordinary bitcoin transactions ready for transmission to the network-- you just save fees by holding off sending them and having opportunities to revise them. More like writing someone a check, then asking them to rip it up and giving them a new one later in the day when you make another transaction with them-- they could settle it at any time, but save bank interactions if they hold off. Netting would be like writing the check at the end of the week. And in Lightning, unlike the check, the risk is eliminated because of Bitcoin magic.

Today the vast-vast majority of transactions exchanging Bitcoin value never show up in the blockchain-- mostly due to systems with significant counterparty risk, indeed. So, some users perform netting on top of Bitcoin to lower their costs and greatly improve their transaction speeds. Is Bitcoin a netting system? No.  Bitcoin is p2p electronic cash, which periodically settles transactions written by users (which may be revised on the fly prior to settlement). Lightning uses the smart contracting system in Bitcoin to allow that ability to revise pre-settlement for transitive flows of funds without a counterparty risk for funds loss, and not just for single hops.