the 90's companies maybe, but the companies on bitcoin are bitpay, coinbase, Mt.Gox (already doomed), etc.
however TCP/IP, HTTP, FTP, etc are all still around. Those are the protocols.
Bitcoin (the protocol) will most likely survive in any scenario, while bitcoin (the currency) will gain value as Bitcoin gains more utility and becomes more easy to use for the average person.
The difference between the internet and bitcoin is that you can invest directly in the protocol, without having to invest in a company. Never in history was there a chance to directly invest into a potentially life-changing worldwide protocol.
The bolded part is extremely important to understand as it makes all the difference.
There have been disruptive technologies before: printing press, radio, TV, phones, internet...see a pattern here? They all have to do with
communication. For information is the true source of wealth in a society and any technology making the spreading and storing of information cheaper, with less friction and more available to everyone is immensely valuable and everyone investing in it is bound to find themselves very wealthy.
Bitcoin is also a technology of storing/spreading information - namely the information of value and ownership. The crucial difference which makes Bitcoin a unique case even among the above impressive list of technologies is that
you can directly invest in the technology itself. From day 1. With the other technologies in order to profit you had to found a company producing the product in question or invest in one. And then you had to battle competition and make sure you invest in the right company. While the technology of mobile phones or the internet is still around and its value is still increasing, most companies which have been involved with the technology are not. With Bitcoin you don't need to do any of that. In a sense it is almost
too easy. Except that it requires deep understanding of several complex subjects in order to make an informed and committed investment decision while most of the world is still skeptical, outright dismissive, or doesn't even know about its existence.