It was far from arbitrary my friend, I'd suggest at least reading bitcoins white paper and some of Satoshi and vitaliks literature.

Take the crypto Kitty case for example. Digital cats are being sold for 10s of thousands. The blockchain enables this very special type of peer to peer exchange of value. Put a golden B instead of the kitties and now your exchanging bitcoin. Ultimately we are becoming more and more digitalized and whether it's a Bitcoin or a kitty we are exchanging code and data, and the ability to that peer to peer, almost instantly, and free of restrictions, is a very valuable asset indeed. Maybe read up on some game theory literature too.
Not sure if you're a beginner or have done due diligence and just have a different opinion(which is fine, I love hearing other folks perspectives). But if you are new to this, it can be overwhelming and seeming valueless, but if you care to go down this rabbit hole, research is your best resource and I think after a certain amount of time spent researching (varies person to person, quality of content you come across etc) I think you will conclude that there is undoubtedly value in crypto and blockchain technology. And if not then cheers anyway mate :)
-best