Proof of work was invented from the start, as an anti-spam measure. The user sends data to a server and alongside of that, sends some proof of work data. This simple system has a downside though, that is ASICS. A specialized ASICS hub of servers, can create as much spam as they wish, because proof of work for the specialized system is trivial to compute. One solution to that problem, is for ASICS hubs, to create the proof of work, and sell it to users. Add on top of that a public database of what ASICS proof of work was sold to who, and you've got Bitcoin. It is really that simple. Instead of fighting the ASICS hubs, you work with them.
This technique, is so simple it should not be even be considered a technology, it is just a technique. A myriad of technologies can use this technique to add some additional properties, to an already existing technology. For example, in the IOT world, an oven connected to the internet, could be used only by a particular key in the blockchain, thus proving ownership to control the oven. One microtransaction can turn on the oven, or turn it off.
The most important aspect of bitcoin, is of course spam prevention. Gmail servers just block any unknown mail provider, just in case they are spammers. When spam was limited to email messages, that was a viable solution for the internet. This however is gonna change.
Synthetic data, i.e. deepfakes, are really gonna take off right now. Synthetic faces of people can be uploaded by the tens of millions to facebook each day. Synthetic photographs of places can be uploaded to Insta. Synthetic conversations can can be uploaded to twitter by the billions. Synthetic songs can be uploaded to bandcamp, terabytes of them every day. Synthetic videos can be uploaded to youtube, or tik-tok, petabytes every day.
The advertisement based free model of posting information on the internet, will go down in flames in less than 4 years.
A new technique is going to emerge, in which we send value to the hosting providers, for our information they are willing to host for us. That value, trillions and quadrillions of microtransactions, less than a cent each per day, it is difficult to track, but it can be done, the question which arises is, what can someone gain doing that?