I have ever heard that before. Some projects like kingspeed was using it. Kingspeed was a failed project. INO was not so good. that's why many NFT projects prefer to use minting mechanism rather than INO. There are some projects were also using ISNO as well.
This word was not booming. The developers didn't interested to use such way to raising the funds from the investors. They still prefer to use token mechanism to raise the funds rather than NFT.
There are so many articles about INO on google.
I know why it's not booming. There's no originality, it's not fresh, it had been used before and failed most of the time. Yes, ICO.
Basic "NFT" should be enough. Investors are not stupid to misunderstand the need to buy something before they start the program.
It had always been that way. If you want faster profits, buy it, take the high risk.
As I seen in my experience most of those who did pay enough reaped their rewards earlier than those waiting for NFT airdrops.
Games or just the basic application. Invest early and you will be paid higher as long as it's a legitimate project.