Bitcoin is for speculation. That's its use-case: it's fundamentally a financial system. It's made a few million people rich and several more million people poor, and started several thousand businesses. That's not a bad track record for something 9 years old; it beats out YCombinator (whose use-case is also "making people rich"), which is almost 14.

I've been on the web since 1994. I certainly found it useful in 1998, but the things it was useful for included:

1.) Looking up Geocities pages for my favorite bands.

2.) Reading rec.arts.sf.written.robert-jordan.

3.) Playing DragonRealms, an early MMORPG.

4.) Instant-messaging my friends.

5.) Earning money through AllAdvantage.com. Think I made about $40 from them off referral fees.

6.) Looking up information for school papers.

7.) Amusing myself with the HampsterDance.

Streaming video existed but was far too slow and glitchy to be worth watching. Amazon.com existed, but my parents refused to buy anything online. My sister was an avid user of Kozmo.com when she went to college, but then they went bankrupt a year later. MapQuest existed, but took too long to load and still required that you print out directions, since you couldn't exactly bring a computer in the car.

By contrast, I've spent over $5K at about 2 dozen different AirBnBs in the last 5 years (and stayed at a hotel...erm, twice, maybe?). I just booked a haircut online, after reading the Yelp reviews and looking up the location on Google Maps. I spent 15 minutes typing up this comment on Hacker News, which I guess is the spiritual successor to Usenet. I don't own a TV, but I watch a bunch of YouTube and my wife's an avid Netflix user. We get almost all our packages delivered via Amazon.

In terms of how much the Internet changed behavior, a lot more happened in the 10 years between 1999-2009 than the 10 years between 1989-1999, and arguably even more happened between 2009-2018 than 1999-2009.