The Texture property is no longer being cleaned up in the Dispose method. Previously, the code destroyed the Texture2D when disposing. Now that Texture is a RenderTexture owned by _converter, it should either be set to null here, or there should be a clear comment explaining that the converter handles the cleanup. Without this, there's a risk of holding a reference to a disposed RenderTexture.

[nitpick] The chroma plane filter mode should be FilterMode.Bilinear instead of FilterMode.Point for better quality YUV to RGB conversion. Using point filtering on the U and V planes can result in blocky artifacts in the chroma channels. Bilinear filtering helps smooth the upsampling of the half-resolution chroma planes.

Potential memory leak: tempTex is created but if Graphics.Blit throws an exception, the texture won't be destroyed and rgba won't be disposed. Consider wrapping the operations in a try-finally block to ensure cleanup:

var rgba = buffer.ToRGBA();
var tempTex = new Texture2D(width, height, TextureFormat.RGBA32, false);
try
{
    tempTex.LoadRawTextureData((IntPtr)rgba.Info.DataPtr, (int)rgba.GetMemorySize());
    tempTex.Apply();
    Graphics.Blit(tempTex, Output);
}
finally
{
    UnityEngine.Object.Destroy(tempTex);
    rgba.Dispose();
}

The shader uses HLSLPROGRAM/ENDHLSL but includes "UnityCG.cginc", which is a CG/HLSL include file. While this may work in Unity, the include should typically be "UnityShaderVariables.cginc" or a pure HLSL include when using HLSLPROGRAM. Consider using CGPROGRAM/ENDCG instead of HLSLPROGRAM/ENDHLSL for better compatibility with UnityCG.cginc, or switch to proper HLSL includes if using HLSLPROGRAM.

I think this constitutes a minor breaking API change—are we able to use Texture2D here? If not, we can note this in the release notes.

Do you think we should expose an API to control this setting?

I believe you should be able to use half, that will save and boost the performance more.

Assuming you are using the legacy rendering pipeline:

inline half3 YUV709Limited_to_RGB(half y, half u, half v)
{
half c = y - half(16.0/255.0);
half d = u - half(128.0/255.0);
half e = v - half(128.0/255.0);

half Y = half(1.16438356) * c;
half3 rgb;
rgb.r = Y + half(1.79274107) * e;
rgb.g = Y - half(0.21324861) * d - half(0.53290933) * e;
rgb.b = Y + half(2.11240179) * d;
return saturate(rgb);

}

half4 frag(v2f i):SV_Target
{
half y = tex2D(_TexY, i.uv).r;
half u = tex2D(_TexU, i.uv).r; // U,V textures are W/2 x H/2
half v = tex2D(_TexV, i.uv).r;
return half4(YUV709Limited_to_RGB(y,u,v), 1.0h);
}