Anyone noticing new projects still raising millions of dollars? Mohash and Dynamic for example, I think new projects will replace lots of top altcoins in coming years and my advice to young investors is to find new projects to mix with their portfolio, remember that Matic, Polkadot, Avalnache are once all new projects in 2018/2019..
Your advice is certainly understandable in terms of investing in what is new to the blockchain. But at the same time, as newcomers will look for these projects, because this requires analysis and understanding of what benefits the project will bring to the cryptocurrency industry. Everything that you mentioned has already been successfully used and developed further. You need something really new and useful to use, and then it will be a worthwhile investment.