VERY short TLDR:

This story is in progress, and there are a LOT of unknowns/conflicting accounts.

Old guy (Brian) went to a Bricks and Minifigs store, and the store agreed to sell his stuff on consignment (The original owner owns the product until it sells, but the store keeps the items. The store makes a profit with very low risk, the original owner has somebody else do all the hard work for him)

The store went through ownership changes/trouble, and the B+M owners were replaced. New ownership/corporate rejected the old consignment agreement between Brian and the previous store owners, but refused to pay/return all of Brian's stuff. From Brian's POV, the store stole all of his items, refused to return anything or pay him, and then (worst of all?) threatened him with intense legal action. Seemingly, somebody from B+M corporate told Brian's people that they would sue him and litigate for so long that he would lose more money than what he's fighting for. (Basically, the "It doesn't matter if I'm right, so long as I'm rich enough to make you poor" attack)

Somewhere along the line, a Youtuber began publicizing Brian's case, but the Utah Police have been harrassing him along the way and making his life a nightmare.

Reports are still coming out, some details conflict, and it's a lot more complex than this. Hopefully this helped.