Bubbles, Bitcoins and Moats

Following a conversation with a group of Bitcoin "enthusiasts", I'm now more convinced than ever that Bitcoin is a hype-based bubble, with many a folk ready to chase the Pied Piper off a cliff.

My (long-winded) question to the group that not a single Bitcoin enthusiast/investor could/would answer was this:

Yahoo was a pioneer in early internet days of search engines. It ruthlessly killed off many a competitor, while crushed any new incumbents - it truly looked untouchable.

Then along came a small startup from Silicon Valley garage that had a shockingly simple user interface and no adverts - in other words, it was incredibly user-friendly and had no revenue streams.

What it did have, was a key differentiator in how it made use of indexing algorithms for search, as well as a revolutionary monetisation model for non-organic advert listings.

And just like that, Google crossed the search engine moat, entered the castle and sent the previously untouchable Yahoo, as well as all of Yahoo's competitors to their deathbed"

So Bitcoin enthusiasts/investors/fans, my question is: what is stopping "the next big cryptocurrency disruptor" from crossing Bitcoins early adopter moat, taking the castle and running off with its riches?

P.S. I'm willing to eat humble pie if I'm wrong here and I'm not saying that the Bitcoin bubble won't get 5x, 10x or even 20x bigger before imploding.

It's also worth mentioning that I have absolutely no doubt that blockchain as well as cryptocurrencies in general, will change/disrupt many an industry for the good.