However, I would like to keep an open mind about things, so I was wondering if someone here could make the case for it without resorting to vague buzzwords.
Don't get your crypto, or more generally finance, news from HN. Reading most comments here it's obvious that most have no idea what they are talking about. They are so far removed from anything finance-related and just jumping on a bandwagon.
The value of web3 is difficult to explain because different aspects of it appeal to different people. For example, the vision of having the same financial instruments globally accessible to anyone with all transaction data publicly available is appealing to me. Imagine you had all of Robinhoods data public and could copy it to make a better product. Wouldn't that be cool? That's happening all the time in web3. The same goes for AMMs, which is a different paradigm than traditional HFT MM liquidity provisioning that's less transparent.
Even though there are many flaws, I can see it becoming a viable alternative to the current fully centralized and regulated alternative, which in many cases is just as scammy. The difference is that the scams aren't obvious because they are not public. Due to the developer platform, market cycles in crypto are much faster than in traditional finance. TradFi breaks just as much as crypto does, but the clock time is slower. On the other hand, this "code is law" approach makes no sense to me, but it may appeal to others.
Perhaps more than being bullish about web3, over the last few years I've become more bearish about web2. Looking at how bad Google search has gotten, how spammy reddit comments, youtube comments, and all social media are, how full of bots twitter is, etc. Many of these emergent behaviors are due to the advertising model that underlies the current web. I don't know how web3 can fix that, but currently it seems to be the only, or at least most significant, push to try something different here.
The metaverse angle is another one. Take games for example. People have always spent money on digital items, even 20 years ago when we played the earliest MMOs. Yes, NFT are 99% scams, but the idea that you want to build a global shared economy with provable ownership around goods not tied to the physical world is pretty obvious.
On the very highest level, I think people are are overestimating how important it is that goods are tied to the physical world (like a company owning physical assets reflected in the stock price). As lives are becoming more and more digital, your amount of e.g. Twitter followers is such an asset as well, not so different from owning a building.
Tokenization and ownership are huge. Ecosystems like Stacks (https://www.stacks.co/explore/discover-apps) have hundreds of Web3 apps already running and providing value.
The value provided by Web3 is simple: now you can program property and ownership on the web.
This changes banking, finance, publishing, social media, etc. It's a huge change because users can take their data across platforms and avoid lock in. Imagine a single social profile that works across platforms (one single profile for Facebook, Twitter, Insta, etc). The possibilities are endless.
I suggest you keep digging in and make up your own mind. Don't let dismissive one liners dissuade you from learning.
Disclosure: I'm a founder of Web3 protocol called Bitfari.