It's not a perfect comparison by any means, but a reason I think people would use crypto (say, loans via smart contract, for a specific case) is similar to why people would buy local vs. national.
There are certain folks who use their money to support small businesses vs. national corporations simply because of their own personal preference. It may not make sense to spend $20 on something from a local business when you could spend $15 and get a similar product from Amazon, but people feel the need/desire to spend their money in a way that it helps someone in their community. It aligns with their core beliefs.
The way I'm relating this to crypto is that there is a minority of people out there who would be willing to get a loan via a decentralized smart contract just because they don't like banks or "the establishment." It may be faster and safer to go the traditional route (just like it would be less expensive to buy through Amazon in my "buy local" scenario"), but there's a minority of people who distrust or dislike the centralized approach. In this way, a use case aligns with their core beliefs.
My subjective view is that as the public becomes more informed about crypto, and a lot of the scams in the space fall away while the cream rises to the top, there's still an untapped portion of the population that will see why a decentralized approach has appeal vs. the traditional route. It may not ever be the majority or close to it, but that doesn't mean there still isn't room for quite a bit of adoption.
Really, most of the arguments that have been hashed and re-hashed in this thread boil down to whether someone is fine with the traditional system or not. I think both ways will exist in the future, but I believe one's adoption has much more growth potential than the other.