wgl: Core profile apparently fails to initialize under opengl32.dll

As discovered in #4050 (closed), when using the ICD, GL Extensions Viewer indeed reports OpenGL 3.3 is supported:

Renderer: D3D12 (Radeon RX 5500 XT)
Vendor: Microsoft Corporation
Version: 3.3 (Core Profile) Mesa 21.0.0-devel (git-2b29ec7ca4)
Shading language version: 3.30


Max texture size: 16384 x 16384
Max vertex texture image units: 32
Max texture image units: 32
Max geometry texture units: 32
Max anisotropic filtering value: 16
Max viewport size: 16384 x 16384
Max Clip Distances: 8
Max samples: 8


GL Extensions: 145

However, when using opengl32.dll from the same build, only 3.1 is supported under compatibility profile:

Renderer: D3D12 (Radeon RX 5500 XT)
Vendor: Microsoft Corporation
Version: 3.1 Mesa 21.0.0-devel (git-2b29ec7ca4)
Shading language version: 1.40


Max texture size: 16384 x 16384
Max texture coordinates: 0
Max vertex texture image units: 32
Max texture image units: 32
Max geometry texture units: 0
Max anisotropic filtering value: 16
Max number of light sources: 8
Max viewport size: 16384 x 16384
Max uniform vertex components: 16384
Max uniform fragment components: 16384
Max geometry uniform components: 0
Max varying vectors: 128
Max samples: 8
Max draw buffers: 8


GL Extensions: 225