If you really feel the projects can make 50x-100x, you should hold the token and not sell it if the price is not hit the highest price. But besides, you feel you must research for more to find if that project really has a chance to increase higher. We don't know if NFT will still exist for a long time since the crypto trend can change next year. So if you think that the NFT still gets attention from people and has a good project to invest in, you can use it for your own benefit and leave it while the project is getting down and search for the other projects.
If you believe in the future in some coins, you can indeed hold it for a long time but I wouldn't really hold very long NFT's; I have the feeling that the hype is slowly fading away . I never understood the real use of NFT's so never invested in it but the only advice I could give to NFT holders is: take profit when you can!
I really don't understand what is the use of NFTs and what are the benefits of holding them in the long run, apart from the hype surrounding it, I see almost no utility.
I think NFT is also one of those trends in the market that comes when the bull market is dominating and its hype will end when the bear market arrives. Now many NFT have dropped a lot and none of the hype stands out.