I am not really familiar with browser mining but this can be interesting and I am sure there would be many who might be interested with this new way of getting into mining without buying the usually expensive gadgets. Though your post can be confusing, to say the least. As long as there is cryptocurrency, there is a big probability that mining can also exist though in Bitcoin this is nothing infinite.
I agree on your statements as regards the indefiniteness of Bitcoins or cryptocurrencies in general. There is a lot to be discussed in terms of the business mechanics (business model) of Bitcoins mainly because of its highly contextual nature. It is very much theorized and criticized thus the attention it receives up to today. And, so far as mining is concerned, it exists because Bitcoins exist. It is dependent to it. Thus, we cannot just separate both subjects especially so one cannot effectively sustain without the other.