Removal of DirectX 9 mode

[shitz.exe]

I have an Nvidia GeForce 9600GT, which is capable of playing the game at around 80FPS @ 1280x720, in DirectX 9 mode.
This card does not support DirectX 11, the max it supports is DirectX 10.1, dxdiag also confirms this.
The latest update (1.36.2.2) removed DirectX 9 in favor of DirectX 11, and the troubleshoot file now also launches the game with the -dx11 option, no longer accepting -dx9.
The game opens a fullscreen borderless black window, then closes.
For whatever reason, OpenGL mode also doesn't start, and I couldn't find anything in the game logs, so it's probably driver-related.

I'm sure many other cards that were perfectly able to play this game (at high settings mind you) are affected by this change as well.

If the DX11 mode could exist side-by-side with DX9 and there was a way to toggle between them, why does DX9 have to be removed?
Also, I doubt DX9 was removed because DX11 will add effects that DX9 wouldn't handle - OpenGL is still a fallback, and that sure won't be compatible with DX11 effects on Windows.
They also can't go with DX11-only, as the game has a Linux version too.

For the moment, I can downgrade the game back to 1.35, but I'm sure that's not gonna last forever, and I'd love to keep the game up-to-date.

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EDIT: add discussion about OpenGL fallback on Windows

[Reese]

I think the way they were doing it before was using obsolete features of Dx9 alongside Dx11. By removing Dx9 support, it lowers development time by not having to make a new feature of Dx11 backwards compatible. Essentially removing the need to write code twice to support the difference in features. I think this is also true for OpenGL support. Essentially 3 versions of code. This is my assumption.

However, going forward, not having to worry about supporting Dx9 means they can make full use of the Dx11 feature-set.

[shitz.exe]

So basically, they had DX9 and OpenGL both being maintained as fallbacks until the current version dropped DX9, only making devs having to code for OpenGL as a fallback.

I can understand that, in that case, I'm hoping they will keep the last DX9-capable version active as a beta channel for a long time.

[Reese]

Originally posted by non-existent:

I can understand that, in that case, I'm hoping they will keep the last DX9-capable version active as a beta channel for a long time.

The way I've seen betas phrased by devs, is that since there's a limit to how many they can add(Steam restriction), they'll keep major important revisions active. I'd say 1.35 is a very important version.