TLDR: It's probably fine, and MS meant it not to leak anything important.
It's worth stepping through this line by line, but it's too long. So let's leave out anything that's fairly innocent.
Essentially though, an attacker must work out what your system is (and this has no obvious Personally Identifying Information), and somehow find a specific driver of OS exploits. It's probably too much work to be worth it for most.
System Information: Mostly innocent. Machine name and exact OS version's there. If someone knew how to get to your system in the first place, and there was a specific issue with that version... maaaybe.
DxDiag Notes: Mostly innocent
- DirectX Debug Levels: Nothing that seems to be problematic here. Mine gives no useful information.
- Display Devices, sound devices, video capture devices, DirectInput devices, System Devices: Driver versions I guess. Driver versions are useful for troubleshooting, so its needed here. If someone knew how to get to your system in the first place, and there was a specific issue with that version of the driver, maaaybe
Disk & DVD/CD-ROM Drives: As above, and how much space you have used.
Preferred DirectShow Filters, Media Foundation Transforms,Media Foundation Enabled Hardware Categories,Media Foundation Byte Stream Handlers, Media Foundation Scheme Handlers, Preferred Media Foundation Transforms
Disabled Media Foundation Transforms
Disabled Media Sources: ALL TEH CODECS. Probably completely useless to anyone.
EVR Power Information: enhanced video renderer information. Nothing much here, I think.
Diagnostics: what's crashed or been troublesome. Looks like this, it's handy:
+++ WER7 +++:
Fault bucket 120429940662, type 4
Event Name: APPCRASH
Response: Not available
Cab Id: 0
On the whole? Not too likely.