Currently Btc acts mostly as a speculation vehicle and also a way to exchange value without using banks or government money.
Let's say you live in Venezuela, what would you rather hold Bitcoin or your shitty government currency that's hyperinflating like crazy? ( Venezuela’s annual inflation rate at the end of 2018 was 80,000%!) Or if you don't have access to banking services then it also makes sense.
For most regular western people it doesn't make much sense other than as a way to speculate/invest/hedge. Cryptocurrencies are not even accepted in most places as way of payment.
From an investors perspective, digital currencies like Bitcoin are a hedge against inflation and a cashless society. Because the total supply is capped Bitcoin is a deflationary asset (unlike Steem).
Some people like to call it digital gold, i don't think that's a bad comparison because often people buy it for the same type of reasons. One of the advantages over gold is that it's easier to divide, transport, exchange, ... That makes it a better form of money.
The argument is then often made that gold is a physical asset while Bitcoin can be hacked. Gold can be stolen to. There has been in history even confiscations of gold by governments (that could happen again).
Does the fact that something is physical instead of digital make it somehow more valuable? Because the value of money is based on trust. You can use anything that is somehow rare. If that would not be the case then why does digital government money exist? It does because people have the expectation that it's worth something and they can use it to pay for goods and services.
Most of the time you see this is a generation thing, at least that's what i noticed. Young people don't know any better than digital so cryptocurrencies seem like a normal thing. While baby boomers rather invest in some hard assets.