There's a difference between an investment in gold coinage which has value as a commodity and an investment in gold coinage for their numismatic value (i.e., as a collectible).

What bitcoin provides is a way to truly own that value by controlling the keys, just as a gold coin provides when you physically hold it yourself. Unlike with the gold, bitcoin is still practical even when held at even relatively small values. There's no way to spend $20 worth of your gold coin, but spending $20 worth of your bitcoin stash is possible (though on-chain fees will sometimes make smaller transactions less economic, but there are L2 solutions like Lightning network to help with that).

Fractional ownership of property controlled by a third party is one approach. Sometimes it makes sense ... equity in a company. Sometimes it doesn't ... such as this numismatic Krugarrand token thingy you shared.

But some investments are made for various reasons.

Art, for example. Ask five people why they invest in art and you'll get five different reasons.

Or this type of investment: https://livestockwealth.com