Physical gold, too. Apparently many think they are holding gold certificates to this day.

nostr:nevent1qqsvvh2ea78k8tdv6dm3tztm2qcy2zrj9768du7ujv2e4av4h7t39zgpz9mhxue69uhkummnw3ezuamfdejj7q3qh8nk2346qezka5cpm8jjh3yl5j88pf4ly2ptu7s6uu55wcfqy0wqxpqqqqqqzkpz5jj

So if paper BTC are "backed by real BTC", people need to understand that repeatability is key. They don't and they don't care.