You can spend it as long as there is someone willing to make the trade. When everybody realizes the lack of consumability, the game's over.
To the extent that Gold is money, by definition, it has value beyond the use of its physical properties.
Besides, it looks nice and doesn't need polishing.
When was the last time that happened in the past, say, 3,000 years?
Gold is not going to lose its allure unless such massive deposits are found that it becomes cheap,in which case its uses will be even more common.
And your first comment is silly.
How about”you can’t eat steel and you can’t burn steel” or “you can’t eat marble and you can’t eat marble” ?
I rather have a case of Heinz pork and beans and a bottle of Jack than a bar of gold