The tech is already there to make NFTs last forever. But the fact is that around 90% of NFTs are hosted on centralized servers. People will eventually lose their NFTs as creators/developers close up shop or move onto the next big thing in crypto. You can already see most NFTs are worthless these days. What you only get is the proof of ownership on the Blockchain. It will say you "own" the NFT, but the content/data will fade away into oblivion. At least, that's the case with the Ethereum blockchain these days. Bitcoin's Ordinals are the complete opposite of this. But it comes at a downside of higher fees and slower confirmation times. As they always say, "you get what you pay for". Maybe there's hope for the NFT industry after all? 
The technology behind NFT is somewhat revolutionary compared to the shitcoins created all these years simply trying to replicate Bitcoin and other successful cryptos in one or another way.
But the hype around NFT is created by influencers which acted exactly as a bubble and it popped a long way back so all these projects became shit now and personally I don't feel there is any room for improvement to the technology from this point.