Every generation of programmers _does_ learn from previous work, and every new platform starts from scratch learning the lessons, and incrementally evolves. A Hello World GUI on Windows 95 will require calling into a complex and undecipherable Win32 API; a Hello World on the web needs one simple line. Platforms do get frozen over time (like the Linux kernel), and people use it to build useful things with low effort. The Linux kernel is a result of incremental evolution: Linus proudly says that it's not designed.

There are severe shortcomings in all platforms that have aged. Why does power management in Linux suck so hard? Why can't we have networked filesystems by default (NFS is quite bad btw)? Until somewhat recently (~7 years), audio on Linux was a disaster: "Linux was never designed to do low-latency audio, or even handle multiple audio streams (anyone remember upmixing in PulseAudio?)". What the hell are UNIX sockets? Is there no modern way for desktop applications to talk to each other? (DBus was recently merged into the kernel). Why doesn't it have a native display engine? (X11?)

Today, it's more fashionable to criticize the web, since majority of the industry programmers endure it. Sure, there are some "simple" things that are just "not possible" with the web (everyone's pet peeve: centering). Yes, you lose functionality of a desktop application, but that's the whole point of a new platform: make what people really need easy, at the cost of other functionality. For an example, see how Emacs has been turned into a web app, in the form of Atom? You don't have to write hundreds of lines of arcane elisp, but you also don't get many features. Atom is a distillation of editor features that people really want.

I don't understand the criticism of transpiling everything to Js; you do, after all, compile all desktop applications to x86 assembly anyway. x86 assembly is another awful standard: it has evolved into ugliness (ARM offers some hope). Every platform was designed to start out with, and evolved into ugliness as it aged. We already have a rethink of part of the system: wasm looks quite promising, and you'll soon be able to write your Idris to run in a web browser.