I think that its quite possible that we can see scaling of 1000x on the linear blockchain, without fundamentally changing the economic/security properties.
Increasing blocksize is just the first thing to do of many engineering optimizations. If you want to climb Everest, you first need to reach base camp.
Even if LN works great and scales beautifully, we will still need that 100x increase in the blockchain that it settles on. LN itself will create transaction demand - people aren't paying $2.50 in fees now to buy a $3 coffee with bitcoin.