How would you define popular then? It's getting more attention which I showed with Google Trends. I didn't say it was going to take out Google lol
I actually do think another search like Google could take them out - I wouldn't say never there. That's exactly what Google did with other search engines with improved technology. I think everybody is rushing to get the best question/answering system out there.
I do think DuckDuckGo can 'take' a small demographic too - I'm guessing people who want to stay anonymous.
Google took over the market when the market was worth nothing. Search at the time ran at a loss for portals. Places like yahoo wanted people to use their directories instead, so they had no incentive to make a great search engine.
Google came in and built a search engine that actually worked, then developed adwords to monetise it, which was a stroke of genius (that seems obvious now). The other companies were all so into building out their portals and directories that they ignored it. By the time they realised Google was going to be "a thing", they were miles behind from a technology standpoint, and G wouldn't sell.
Since then, Google has just maintained its marketshare as the market has grown. Internet speeds got faster, more people gained internet access, and they turned to Google because they had the best tech and biggest brand.
Displacing a market in its early days, when its value is basically nothing, then riding the trend upwards is an entirely different achievement to coming in today, and displacing Google's stronghold in a $xxx,xxx,xxx,xxx market. Myspace, for example, was destroyed in the early days of social media (did we even call it social media then?) when the market was worth hundreds of millions, rather than hundreds of billions.
If you watch how huge organisations die, its usually because the market changes and they don't adapt/find new markets, rather than someone stealing it away from them. For example, CD players were a huge industry in the late 90s. In the 2000's, apple came in and built the iPod, which rode on the back of a number of trends: internet speeds increasing meaning people could download mp3s in a reasonable time, hard disk drives being large enough to store lots of tracks, the technology being small enough to fit in your pocket, etc.
They took the market share early, and then rode the trends. No one displaced them, because they got in and dominated early on. It wasn't then another mp3 player that killed the ipod, rather other trends: mobile internet getting better, phones being able to perform all the functionality of mp3 players, etc which led to the smart phone market destroying the market for mp3 players, and largely killing the ipod (apple saw this earlier though, and lead the charge in effectively killing its biggest market with the iphone).
The death of Google search won't be another search engine, unless Google is incredibly stupid. It'll be some way of finding things we can't even imagine yet.