Now, with things like AWS, Terraform, increasingly converging popular programming languages, frameworks and best practices like tests, code review etc, in some ways things are less complex.
And that completely ignores how well PHP works for standard web sites.
So, if anything, I would say that things peaked with very understandable deployments about a decade or so ago. Sure, we now have "web scale" orchestration frameworks for the giants out there, but... I question how well this actually solves problems that folks have.
Worse, I also challenge that anyone really has a handle on scale. Walmart's site, as an example, was completely garbage today when they released there silly supply of PS5s. In all sorts of ways that showed that eventual consistency is the unnamed assumption in how all "web scale" things are created.
Even inside AWS there's no standardised way of doing deployments. Are we using EC2, Lightsail, Lambda, Elastic Beanstalk, EC2 with ECS, Kubernetes? For databases, are you hosting yourself or with EC2 or using RDS? Or are you using containers? Or Kubernetes? Too many options.
Pre-AWS, however, things were much more standardized: Linux servers. Or Windows for 5-10% of cases.
Beyond that, in some instances even for simple apps there is less complexity once you know the technology. That's not complexity though. That's a buffet of useful options.
Good architecture decision are even more critical today.
You're wrong. Complexity has increased by a huge magnitude so much so that it's actually unmanageable by a single person.
What's going on in your case is that the complexity of all of this has been abstracted away from you by amazon. They have entire teams of people making sure you don't have to deal with the actual complexity. That's the difference. This isn't an actual abstraction in the same way a high level language abstracts the details away from you. This is an abstraction where a team of people take care of you. It is not a true abstraction because you cannot wield this abstraction yourself in the same way you can wield a high level programming language.
Make no mistake, the actual complexity of it all has increased by huge orders of magnitude.
Amazon abstracts complexity away by having someone else deal with it. Big difference. One would imagine software progressing towards abstractions that are simpler and allow one person to do more, what we are getting is instead abstractions that only make it seem this way when in reality it's going in another direction.
Complexity is increasing to the point where one person can do less, but companies like amazon don't let you realize this by hiding the true complexity behind other people who deal with it.