bitcoin is still bitcoin, it has never changed but people's usage has changed and most people just prefer to use bitcoin as an investment rather than a currency.
But I think it's not as serious or bad as many people think. Because at the end of the day, whether bitcoin is a currency or an investment, it is still decentralized and most importantly, it still benefits those who invest in it. An invention will truly become useless when it is not used or does not bring any useful use or use case. But in this case, bitcoin has brought great benefits as a decentralized asset. It not only helps people become aware of the concept of decentralization, privacy... but it has been helping many people improve their economy and have a better life.
So, even though bitcoin is not used as a currency and is only considered an investment, it is not that bad.
The "real" purpose of bitcoin was to be used, and it's used, sure it was intended to be used as currency but it is used as an investment yet that is still a way of using it. This means that as long as it's being used, then I think it's fine, we do not care "why" it is used, we only care that people are using it.
To be fair, I do use bitcoin on my daily life, because I have a loan from an online place, it's basically a bank, literally legally registered in my nation, but they do accept bitcoin payments as well, so I am repaying 30% of my debt in bitcoin, rest is from regular traditional banks that I pay in fiat. Which means that bitcoin is growing more in the sense that we use it as currency too.