Their state is in NO WAY attached to the original server. A user interacting for example with pizzaorder.asp who interacted with the form a dozen times and a dozen round trips to the server were made ANY combination of machine could service the dozen request with no data confusion. STA and Thread-Affinity are a relic of the past. SOAP webservices are a snap to build. A new thread-safe object oriented API that has much more than the existing Windows API ever had.
Any programmers using the API even from notepad achieves thread-safety.
The NGWS API are objects that can be accessed by reflexion. They include that and calendar functions for Iran, Japan, etc. The Crypto APIs have for example dozens of encrytion capabilities and styles. But experienced programmers are not forced to buy because of lack of infastructure.