Setting aside the fact that BitTorrent came about long before BitCoin was a glint in Satoshi's eye, it's still massively used for content distribution, on top of being a foundational technology to several industrial applications: Apache Spark, for example, uses BitTorrent to shuffle/broadcast data around cluster nodes.
Even when BitTorrent alternatives are used in its place (such as IPFS, Dat, or Kademlia), BT was still a massive influence in all of their designs, and to the design of any other DHT that came about after its release.
All of these, plus other systems that are (in abstract) similar constructions, have several industrial applications for asset distribution (Netflix uses IPFS to distribute container images internally [0], Uber and Alibaba do similar things) and network management (DNS for example, is really just a DHT, as are several other network protocols)
Ever since BitTorrent came about, it has unequivocally been a resounding success. It never for a moment had to look for applications, there were already plenty since day one.
[0] https://blog.ipfs.io/2020-02-14-improved-bitswap-for-contain...