You're quoting public (routing) channels. Most channels are private. LN is a velocity and transactional layer. The difference between the LN and blockchains you mention is that I can't run a node on Liquid because it's a federated model of 15 special companies (although their dynaFED upgrade will certainly help this). And WBTC is a centralized product run by a faux DAO of 30 shady companies including BitGo. Lightning is cool because there is no LN network, but your LN network. It's a bunch of different implementations working together and interoperable through BOLT spec, sort of like the internet protocols.

The simple, light, and free LN wallets available on desktop, mobile, extensions, etc, are getting better. The direction is towards self-custody and they include an LN node. When Zerosync and ZKs hit, we'll have wallets that are fully validating with a full L1 and L2 node on your smartphone. Add in splicing, scripting etc, and the lines between L1/L2 get quite blurry. I mentioned previously the directional design pattern of Lightning. You have to consider that when considering federated chains like Liquid, or ancient merge mine products like Drivechain. How are sidechains competing with something that's instant, nearly free, fully validating, and moves between layers seamlessly? By integrating it, just like the CEXs have already done, and just like every other blockchain eventually will do.