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Why I think it's highly unlikely:
I think one of the problems is that it will be more expensive for people to use bitcoin than fiat. We can also say that it will create a huge load on the bitcoin network to make all these transactions so it will probably be even more expensive and slower because of that. Also worth mentioning that bitcoin is still pretty volatile and I don't see it becoming more stable in the future. And the whole system will depend on the miners and if there gonna be any problem with them, then the system will suffer. And another thing is that when people will see how volatile bitcoin is, they will try to exchange it to more stable asset that will dump the price of BTC as well.
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So you realized that there is an open secret of a scalability problem which occupies the minds of different developers. Second layer like LN is one of decisions was found (IMO not the best decision, but is can help for a while), there are some other as well. So right, bitcoin can't work the same way as popular payment-processing systems like Visa or Mastercard right now, but it is a matter of time and finding some new solution, and I'm sure developers will find some brilliant decision in the nearest future. It doesn't mean we should hurry with that but we should not worry too much as well.