Exactly. LN is like opening a "tab" in a bar. You ultimately settle on the chain, just like how you settle the final tab on your credit card.
LN is an unnecessary solution to a made up problem. Other cryptos have proved that much much more transactions can be easily processed by merely increasing the blocksize.
Increasing the blocksize makes running a node much more expensive (due to storage, mainly) which in turn makes the network less decentralised. Bitcoin (rightly) selects for decentralisation over transaction speed, hence LN as an L2...
As someone who runs a full node, this is not accurate at all. Space is cheap, bandwidth is expensive. I frequently upload > 1TB a month via my full node, if blocks were twice as big and full, then I would be uploading > 2TB a month. How many people in the world have an internet connection which can handle that? Then you have to process each block, the bigger they are, the most computation needs to be done. Everything is a trade off, Bitcoin has chosen decentralization over throughput, other chains have chosen differently.
In India there are MOBILE plans that allow you 2GB everyday for $2 per month! My broadband is unlimited data at 30 mbps for our $10 per month. Do quit this bullshit argument.
I don't run a node but I imagine if you're conscious about bandwidth you can choose not to upload anything (or very little) and still have the opportunity to maintain an up-to-date copy of the blockchain.
100 Mbps internet connections are really common nowadays. 1 TB of bandwidth in a month is really nothing. I use more than that just for Netflix and torrents.
(I used it back when it was in beta to buy something from blockstream, but that was it. Back then it was an extremely complex process.)