Decentralized Finance (DeFi) and speculation is the most obvious use case right now, and I don't think that will change over the next 1-2 years. But I'm convinced that many more will follow.
I was just a little bit too young when the dot com boom happened, mostly playing games and hanging out in IRC channels during those times. I always imagine how cool it would've been if I had been a capable developer back then. The blockchain ecosystem(s) are the first technology in the last 10-20 years that feel the same - it's incredibly early with people hacking away trying to build basic things using a completely different model of the world.
I didn't "get it" for the longest time, ignoring cryptocurrencies for many years. But once I "got it" it completely changed my way of thinking. I don't know about the timeline, but I'm more convinced than ever that it's the next big thing and that the centralized internet as we know it will no longer exist in a few decades.
For the record, I hold neither BTC nor ETH (besides what I use for development) and I didn't get rich from it.