There are so many altcoins now top-listed in the market that it can be said whether they are good to hold long-term in reality. It's up to you to choose which of the top 20 you want to buy. Just the top 10 in my opinion are Ada, Matic, Bnb, Tao, Doge, Pep, Bonk, Xrp, Arb, and Sol.
These are just my choices that, in my opinion, will actually be released in the coming future, to be honest, but there are others out there that I haven't mentioned that I know if there is still potential.
What do you mean to be released in the future? If they are among the top 20 then that means they are already released, but I think you mean those coins will pumped more in the future. I agree for the most of them, while for some not because they are only just a meme coins anyway and we all know meme coins, they can only come and go.
When I say go, I don't totally mean they can now get delisted since some meme coins are still there like for example Dogecoin but what I only mean is that their value will now go down and not recover anymore. Just take a look at DOGE. I know it rise a little but it is still struggling to reach its past ATH.