Probably somethin Exponential Audio are responsible for. It happened to me. Let them know and it will probably get fixed - although they obviously didn’t take any notice of my email.
Did the installer ALSO install a VST2 version of the plugin? The Ozone Elements free version did this and I had the same result. I think it was blacklisting the VST2 version or there was a conflict between them. Anyway, I reran the installer and only selected the VST3 version and it was fine. I have noticed in the past that Cubase doesn’t like when there are multiple versions of the same plugin (either 32/64 bit or VST2/VST3).