Higher-resolution ones definitely do. That's why you only get Widevine L3 on PCs and Macs, which most content providers limit to 720p or below.
You need something else (like Apple's FairPlay or Microsoft PlayReady) beyond that, and these definitely check your HDCP version. I believe 4k output commonly requires HDCP 2.2.
FairPlay on macOS might be based on obfuscation still (there was an interesting article on that here some days ago), but high-resolution playback on Windows definitely does involve the GPU driver somehow.
You need something else (like Apple's FairPlay or Microsoft PlayReady) beyond that, and these definitely check your HDCP version. I believe 4k output commonly requires HDCP 2.2.
FairPlay on macOS might be based on obfuscation still (there was an interesting article on that here some days ago), but high-resolution playback on Windows definitely does involve the GPU driver somehow.