It can be shutdown by those people who create it so I don't really think its best option to have digital real estate since scamming is rampant and might we can spot one of those especially if we don't have proper documentation of such thing.
Yea, don't get in, if you don't understand. I speak from experience, I purchased few Bitcoin ordinals, and lost them in paying transaction fees, lol.
Regarding shutting down, they can't be since everything lives on blockchain.
Depends on the logic and what you mean by shutdown. Think of it like ownership and usage, the usage can be shutdown but the ownership won't be. Imagine NFT right, if you own it then you own it, there is no reverse back there, you will always own it until you sell, but the way it looks like an image? That part is on a server, so if the server goes out, you will own something that is not an image anymore, it will not look, it won't have anything, it's gone, you still own that, it just doesn't show up as an image.
Like for example you have a metaverse world, it is like roblox basically, or minecraft whatever, if the servers go down, sure the land you own there is still valid, but the game is gone, the world is gone, because server is gone.