The reason for this is that the Ironlake graphics architecture is not ivy bridge or sandy bridge
It's Clarkdale/Arrendale gen technology which, while the hardware strictly speaking supports the extensions, does not have these features implemented in the relevant graphics drivers.
You could take a stab at adding them yourself if you have experience with driver programming.
The relevant section, in case the link goes down:
"While Ironlake (Clarkdale/Arrandale) -- the generation of Intel
hardware prior to Sandy Bridge -- was designed during the OpenGL 2.1
days, much of the OpenGL 3.0 / GL Shading Language 1.30 functionality
can be implemented for this hardware. As Intel Linux customers were
quick to discuss when sharing this morning there's now OpenGL ES 3.0
for Sandy Bridge (the embedded/mobile GL variant), driver developers
quickly lose interest in older hardware.
One Phoronix reader pointed out this bug report with commentary by
Kenneth Graunke from January:
Team Fortress 2 requires some functionality from OpenGL 3.0 and GLSL 1.30, which we currently only support on Sandy Bridge and newer
hardware. Unfortunately, Ironlake and earlier currently do not.
It should be possible to implement the missing functionality on Ironlake. The code is open source, and the hardware documentation is
freely available on the web(*), so in theory, anyone could make
progress toward this.
Sadly, our team is extremely busy working on newer hardware and is unlikely to have time to implement GL 3.0 support for Ironlake...at
least not any time soon. I sincerely apologize for this; we'd all love
to see it happen too.
Basically, Intel Linux driver developers are busy working on newer
hardware and other features, so missing functionality for older Intel
products likely won't come. But since Intel does provide NDA-free
programming documentation, other capable developers should be able to
provide the said features. This bug comment was in response to
Ironlake not working for Valve's Source Engine games on Linux.
While I do own some Ironlake hardware, I would much rather see Intel
working on the newer hardware support. Even if the Intel i965 DRI
driver implemented the necessary GL3/GLSL1.30 features for the Source
Engine games, it would still be damn slow. It wasn't until Sandy
Bridge that Intel graphics really got their act together in terms of
integrated graphics performance. Ironlake isn't too capable and the
newer (and yet-to-be-released) hardware is much more exciting and will
open new doors. Intel also, obviously, wants you to upgrade your
So the simple answer is: Intel doesn't care enough or have any incentive to implement the features, but at least you /could/ implement them if you wanted and had the skillset/funding to do so.
I would recommend upgrading your hardware if you need OGL 3.x features as they are not and most likely will not be supported under the Ironlake architecture.