When exactly do you think the web was "decentralized"? The web the majority has ever interacted with has always lived on someone else's server. Self-hosting has always been rare.
It's weird seeing people talk about some mythical history where the web was somehow decentralized.
Decentralized doesn’t mean that every website is distributed to user-local edge servers, it means that there isn't a single point of failure of the web (that is, the web is decentralized, individual sites are still, separately, centralized.)
The emergence of central dominant vendors for key services reduces that (AWS, MS, Google, and CloudFlare are each capable of disabling a lot of the web with a failure; and there are backbone providers that can have similar effects) somewhat, of course.
This idea ignores that 1) there's always been points of failure for the web and 2) there's reasons the dominant players became dominant.
The web in real terms requires infrastructure for content to be available. Without that infrastructure you've just got dead links. But this has always been the case. There's no golden period to go back to.
The dominant players in the infrastructure business can end service for individual customers but they don't run everything. You can spin up a server and point your DNS records at it and be online if CloudFlare drops your site. They exist because it's cheaper to buy infrastructure in bulk and sublet it but that doesn't stop anyone from making their own server on their own infrastructure.
In the earlier days of the internet, there were no two companies you could pick who, if they had large-scale server issues, would take down a significant portion of the web. Nowadays, if Cloudflare & AWS have a bad day on the same day a lot of businesses may as well just send their employees home, such is their outsized impact on the internet. (And the internet on our lives, of course.)
This happening "for a reason" doesn't change the fact that what is now the case was once not. In 2001, if a particularly well known tech vendor screwed up their DNS, their product website would be down and everyone would shrug and go about their day. In 2022, if a particularly well known tech vendor screws up their DNS, more than 10% of the internet falls over.
The fact that I can spin up a server is true, but doesn't help me when I can't pay my bills online because a very large shopping website has gone down.
> This idea ignores that 1) there's always been points of failure for the web and 2) there's reasons the dominant players became dominant.
It ignores neither. The web (and the underlying internet more generally) are decentralized systems by design, but over time (because its a lot more convenient and efficient when you aren’t, say, experiencing a major widespread disaster) a lot of key functions have progressed in the direction of centralization, because unlike the prople making the original concept, most users aren’t making decisions with a nuclear exchange targeting critical communication nodes as a significant part of the threat model that their resiliency plans address.)
These aren't binary transitions (nor are they entirely monotonic), and there are very good reasons people prefer more centralization for the uses the internet has evolved to fill. But it is a real change over time.
It's weird seeing people talk about some mythical history where the web was somehow decentralized.