The same question was archived on r/trackers. Would like to get notified when a compatible tracker is available for testing, it’s not even clear if there is an implementation just yet.
The specs are here since 2017 https://www.bittorrent.org/beps/bep_0052.html
Compatible clients are available, at least qBittorrent (from v4.4.0) and BiglyBT.
Restored security (SHA-256) is the first reason.
But what’s most interesting to me is the single files hashes.
Each individual file will get it’s own hash, reachable from the DHT. It also seems that there will be some kind of standard hashing method allowing to get unique reproducible hashes (no more piece size or parameters). Two persons would always obtain the same hash for the same file even for different torrents. This is all to reduce swarm fragmentation.
So it would be similar to IPFS (except this one broke his promises by introducing several multihash versions…).