If a coin introduces a completely new technology that enables a different function and is sustainable in the long term, does it have the potential to be a worthwhile investment?
There is never an easy answer to this one otherwise everyone would nail it. You really need to either do an insane amount of research or just gamble and know there is a good chance you might lose all of that investment. Start following smart people amd check our their recommendations and go from there.
Unfortunately the majority of new coins are a complete gamble, because a great number of them serve no purpose or are scam coins based on the pump and dump scheme. Generally, you'll need to read their whitepaper, see what the project's goals are and most importantly, are they feasible or are we talking about a panacea that can't be implemented on the real world? Are the developers organised and is there a community that supports this project? All these questions play a vital role to determine if a new coin is worth investing.
I'm not really into altcoins and investing in new projects because I can't bother researching if it's worth it or not, thus, I tend to stick to Bitcoin. However, Binance recently listed SEI and Cyber, both of which look promising and decided to involve myself into farming them. Binance also usually lists projects that aren't scam schemes so you may want to be on the lookout for any other coins that might enter their launchpad.