Another topic from believer who so sure that bitcoin will replace fiat in the future. It may happen in the future when digital technology are adopted by most people in this world, but 2020? Nope you will still need fiat money for your daily needs. It is impossible to live without fiat money if you live in an area where bitcoin is not accepted as a legal payment method.

yes right, fiat will still exist but more and more people will use bitcoin or altcoin for payment. inevitably the popularity of bitcoin is getting higher

Well bitcoin can not end the existence of faint paper money, because the bank system will always strengthened the monetary policy, and will always fine to manipulate the government over bitcoin and other digital currency transactions because it decentralized. Bitcoin is already used for payment even in this 2019 for goods and services.

But saying at 2020, we all be using BTC, I guess no, fiat will exist maybe for another century at most.  Banks will resist the evolution, most will stick to the old paper money and besides stating an event that will take place after a year when only a portion of 1% of the world population is using, that is actually nonsense.  Im very positive with cryptocurrency replacing fiat in the future but not this soonest, and not everything is bought in USD because it is not the only currency in the world.

Crypto and fiat need to be use together which is the reason why we see some project owners which integrate the crypto to fiat payment system.
But, this was not the OP presumption cause the Bitcoin market will claim another ATH next year May and during that time a lot of Bitcoin holder will use some of their profit to buy some luxurious things this was what the OP meant

2020 indeed sounds unrealistic. It's easy to be blinded when you and your friends use smartphones to pay for everything, so it seems like turning to Bitcoin on global level is a short-term thing. However, I believe the majority of the world still mainly used cash for payments. Another important thing is that even when people are ready to turn from fiat to bitcoin, we still will have to wait for the governments to recognize Bitcoin as legal tender. It won't be long afterwards until the retailers make their move. But it's still a matter of decades, not years.
Not to mention that full-scale adoption is not an option for now due to technical restrictions of Blockchain.

Well you can already buy anything with bitcoin right now, you can find many places that sell goods for bitcoin directly or you can use bitcoin indirectly to buy things from amazon or other popular sites, or just use bitcoin debit cards, the problem is they are not as popular or as out there as the fiat ones, we want to use bitcoin in our daily lives but because we are part of the society which relies on fiat and banks we can't always do that, we have to pay our taxes with fiat we have to buy from the supermarket with fiat, there is no escaping that, and the only way we could replace that is if bitcoin gets implemented as a global payment method, and for that to happen we have to be a be a voice that can be heard so that they will notice that we who use bitcoin are not a small dying percentage of the world the community has to rise up.