I dont think that at all.
Neither do I, where I work, older versions of our tool (naively) had a lot more draw-calls than this (something like ~6-8x that amount...) with no form high-level culling what so ever, completely brute-force approach.
In this version our renderer took about ~35% of the program's time on a single thread (but our app is not single-threaded so) on PCs with intel core i5/i7 chips and mid to high spec graphics cards.
Really there was no reason to have that amount of draw-calls when most of the geometry may not be even in view most of the time (except in the worse case scenario).
I believe a combination of very high-level CPU-based frustum culling, geometry instancing, instance level GPU-based frustum culling and indirect draw-calls should be more than enough to make this (in most cases) a none issue both CPU & GPU wise and all of this is possible in OpenGL and should be in DX11.
At this point there shouldn't be much of a reason to parallelize draw-calls as the actual number needed should be a lot smaller unless you legitimately have many uniquely individual pieces of "geometry chunks" in view to render even when using instancing.
In this case OpenGL has multi-draw commands which also has variants of both indirect & instancing (and together) so there must be a way to more efficiently deal with that case too.
Does D3D11 support such draw-calls? As far as I'm aware it doesn't.
I think the only real advantage of Mantle has in terms of draw-calls is the ability to more easily parallize draw-calls with almost linear speeds per core added.
Anyway Mantle isn't just about speeding up & parallelizing draw-calls.
The 100k figure is for having the GPU feed itself draw calls. This is still only going to be possible under an API like Mantle.
Isn't that true for indirect calls in both OpenGL and DX11? I mean you can have shaders manipulate draw command buffer objects. The only thing CPU side is adding execution/dispatch points. You have similar API functions for dispatching compute shaders, indirect dispatch commands.