[alistproducer2]

The blockchain is not what's responsible for all of the things you describe; rather, it's the dominant algorithm for psuedo-randomly distributing the ability to modify the block chain, called proof-of-work (namely Satoshi's version). There are other, just as computationally wasteful algos that try to be memory hard as opposed to cpu-hard (Cuckoo cycle PoW for example.

Lots of folks are working on different, less wasteful ways of making blockchains more resistant to attack - the most well-known of the alternatives being proof-of-stake which is essentially a betting scheme. It's a fascinating area of computing if you go beyond the hype over the BTC price.

[nsxwolf]

Ok, but what are blockchains doing right now? Does my iPhone use them? Facebook? Small businesses? Tesla? My doctor? Who/what??

[alistproducer2]

Lots of financial institutions and other businesses have been researching ways to replace systems with private blockchain technology [0]. This is just one of several business partnerships exploring ways to integrate the tech.

Unless you're buying/selling or paying for things with cryptocurrencies, then, no, you probably aren't encountering any blockchain tech right now.

[0]: https://entethalliance.org/members/