Did you actually found cases where that was limiting ? Half of the machines sold nowadays have way more than 4GB, which is already crazy amount of space for a win32 (even LCL) binary.
Yes. Many of my customers do not want to use a PC at all and keep asking for an iPad app. When I tell them that they can use any old junk laptop off of ebay with Windows 2000 up it helps. I had one ask me if I could support Windows 98 a few months back.
I have customers with EEEPC 701s which are useful as they have an SSD so no moving parts. An early 701 only has a 2G harddrive let alone 4G of RAM. Some of them will be using really lean window managers and will not appreciate me forcing them to install Qt or GTK.
Personally I develop on a Dell D630 as it is one of the more powerful laptops that still has a real RS232 port, which I need. The USB adaptors really are not good enough for what I do.
Also the program is downloaded over the Internet so the smaller it is the better. I have customers in places with very poor Internet connections. At some point I may have a security problem and need to force customers to update, I will not be popular if this happens when a customer is using their mobile phone as an Internet connection and just wants to get the job done.
Smaller, faster, leaner, more backwards compatible, no dependencies on other libraries. This is what I need and I think fpgui does the job. I really appreciate those who made the effort to develop it.