It's a matter of mindset (http://www.sandon.it/node/58)
When I wrote the QC entry about Datasnap 2010 HTTP client missing proxy support, I marked it as a bug. It was later changed by a sysop to an "enhancement request". That simple change shows why Delphi is in the actual state. It's a problem of mindset. Embarcadero people still lack the mindset to deliver applications made for the 2010s.
You may think "you're implying too much, it is not a bug really, just a missing feature". Look at it from the sysadmin going to deploy an application. You have carefully installed firewalls/proxies to protect your network, authorize, filter and log HTTP access, and reduce bandwith use. And now someone gives you an application to deploy which has no way to work across a proxy. In 2010. Do you think it is an application that just needs to be "enhanced", or do you think it is an outdated buggy application, written by incompetent developers?
Proxies are not the latest, cutting edge technology. They are a basic tool employed by any sensible organizations, even small ones (open source ones are available as well) to keep some control on the ever increasing internet traffic and threats.
And the question is, which kind of organization, which kind of "enteprise", Delphi product managers and developers have in mind when writing the feature set specs? In the past ten years they've been keeping on overlooking many basic building blocks to deliver real applications. Most of them look prisoners of a time bubble, as the IT world is still that of 1995 or little later, a simple client/server world of companies with some Internet access, IT departments still in their infancy, and small development shops of self-made enthusiasts.
Oh yes, they like to talk about Json and REST, some buzzwords are always useful to try to promote the product, but behind them there's always a too simple, even less than "basic" implementation. You have REST, nice, it can't work across a proxy...
This a problem of mindset. Delphi management has been unable to change it in the past fifteen years, and adapt to changing times. They just tried the wrong "big" changes to follow fashion (Linux, .NET, MacOS), but when it comes to face the reality of professional developers every day work, they look unable to understand that the basic needed features are no longer the simpler ones of many years ago, and that Delphi needs to adapt to keep on fighting in the professional development arena. Developers and their customers expect much more today.
I could agree that service discovery, clustering and automatic failover could be "enhancements" to Datasnap, but proxy support (and encryption and... ok, you know)? C'mon... please, change your mindset. It's 2010.