Probably they are, both the arts, paintings and as well as the games. They will be put to test once another trend comes that will take the hype that's with the NFTs.
I think those digital arts that have started to be priced as that much have started the craze when there were NFTs that have been sold millions.
I only see potential value in gaming world, there will be limited number of popular gaming NFTs since you cant just make good games every week all the time. When it comes to art, anyone can draw anything and keep doing it no matter what. We already see how many new art NFTs are coming to market every week, its just sick that people think every single thing will be worth something in the next few years. Please be careful what you buy.