I don't think Everyone will move to INLEO, as there are people who develop other dapps, those loyal to them, and those who don't like @khaleelkazi for one reason or another.

Even if everyone moved to INLEO now, I don't think it'll make the blockchain unhealthy or less decentralized because everything is still on the blockchain, and people can just create their own interfaces if they became unsatisified with INLEO, and it's not very hard.