You're starting off by being skeptical about crypto and asking what's "not-a-total-scam".
That's a good thing when it comes to crypto. The less you trust other people makes things look better for crypto.
Crypto is better positioned to deal with a lack of trust in a transaction than any traditional business or government. It's designed to be trustless. You can (and IMO should) be a paranoid schizo and worry that every single human is trying to rip you off at all times: but in crypto, code is effectively law, and everything is effectively transparent.
You don't have to worry about somebody completing their end of a bargain when you can verify that money is held in escrow and contractually held until conditions are met and you can even examine every line of code. Even if somebody wants to rip you off in this circumstance, they can't.
You don't have to worry about how many tokens are in circulation when you can look it up and verify any time you need to.
How do centralized systems deal with proving that they're trustworthy? They don't, unless you trust that government and law enforcement is able and willing to find every scam, lying business and institution, and finding corrupt con-artist out there.
And they're not. An example I like to use to illustrate this is the concept of naked shorting in the stock market making it such that it's impossible to know how many shares are even in circulation to set the prices. See this story.
https://www.reddit.com/r/Superstonk/comments/rsaevv/in_march...
> In March of 2005 this guy bought 100% of shares (1.1M shares) in a traded company to prove the corruption. The next two days that same stock traded 50 million times and dropping the price 99% in two hours. All this with LITERALLY NO SHARES AVAILABLE TO BORROW OR SHORT.
The NYSE has been around for over 200 years, seemingly can't or won't eliminate this practice, and if you don't trust them what recourse do you have? Imagine if trading was implemented on some kind of crypto though: you can instantly verify exactly how many shares actually exist with zero possibility of a lie.
Your question is asking about specific projects, and I can name and espouse the interesting and unique benefits of many, but I think you should start over and look at the basic attributes of crypto that centralized systems cannot provide.
PS: Speaking of being skeptical, it's a little odd that you create a random account and just dart in to make a couple of posts about crypto. Is this somebody with an agenda or somebody trying to farm accounts with hot-button topics here?