Bitcoin is still very much used and adopted all around the world to this day. It has been accepted by organizations and payment gateways all across the world. So what about Altcoins? Are they worthy to buy in future? To predict the future is very hard. In the cryptocurrency world, prices are very volatile. Dealing with the issues of transparency and scalability problem, might effect cryptocurrencies in the future.
Bitcoin is not really circulating as much as you think in some developed countries. all are fomo posts about bitcoin to increase investor confidence. Basically, no one wants to trade and accept high volatility assets, which will affect their future revenue and business strategy. If so, they will only accept about 10% and the rest will be fiat money.
actually, we should not expect cryptocurrencies to be accepted for payment everywhere. they just need to increase the value after each year and make an asset to trade is more than enough.