I don't think web workers are a good design. They are maybe simple, but lack in flexibility and capability. E.g. if I am not mistaken, you cannot control animat

I don't think web workers are a good design. They are maybe simple, but lack in flexibility and capability. E.g. if I am not mistaken, you cannot control animations from a web worker. You also have to communicate with them using strings, therefore there is considerable overhead. JavaScript and the related ecosystem in the browser lack a number of things, that are then patched over using additional complexity such as web assembly, bug handling/ feature workarounds in applications, mobile apps that you basically have to develop, because the web isn't useable/ performant enough for some stuff. Of course we have some extra experience now and it is easy to criticize in hindsight. E.g. the decision to make JavaScript less LISPy was perhaps a good decision for it's large adoption but longer term the homoiconicity could have been used for easier generation instead of e.g. stuff like WebAssembly. We also know, that stuff like Clojure(Script) is possible now. We also know, that we really want a native 64bit integer type instead of hodge-podge solutions with reduced precision of 53 bits or big decimal with worse/ complicated performance characteristics. For the last 12 or so years, the web and related technologies became an application platform and a video delivery network with demands that rival native applications. We even use JavaScript on the server side through Node.JS. This has enabled tremendous things to happen but it is also perhaps the least stable platform to develop for. The web actively breaks some of the more complex applications that it has enabled precisely because the foundations are not solid enough. The current state of affairs is we keep piling on new and shiny APIs and technologies, that perhaps have considerable merit but we don't really fix the broken things in a way normal devs could keep up. I mean, how do you imagine to keep up, if even GMail, Google Maps, YouTube, Facebook and all its web apps, even major news sites and other applications backed by big companies still have rather obvious bugs in these products? I guess, "move fast and break things [for the later generations to fix all this mess]" it is.