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Well, I guess something will need to be done at one point. The usage will inevitably increase anyway, especially at the market expands and Bitcoin matures. By second layer, do you mean LN? Would that be a working solution that could work at a large scale while also preserving the main aspects of Bitcoin, such as decentralization?
Yup, LN. There is simply no other solution!
The blockchain has right now 580 million transactions witht a size of 300GB, not that much, doesn't sound impressive except that if we look at the top 3 card processing networks (visa/mc/upay) they are handling 1.2 of that every day! Moore's Law is dead and buried you can't force a home user to keep a record the size of a multinational trillion worth company in his room and add a new hdd every week.
But, again but!, I'm almost sure that nothing even close to migration to LN will happen.
More likely, and unfortunately people will switch to web wallets and use those to pay for things or transfer money since those wallets can offer close to zero fees when it comes to transfers between users as they don't have to settle balances on-chain. And ...we're back to square one.