I don't know about Simon, but I am not claiming that an Oracle stand alone project would appear (or be) more professional; my only interest in that is to have the ability to continue serving current and future clients who require Oracle. What I do think is that it would make the remaining OpenACS project look more professional.
How many potential large users (since an installation using Oracle is more likely to be large than not) have silently left after doing a test install and finding Postgres syntax in sql or xql files clearly intended for Oracle? When someone is in evaluation mode that sort of thing can send them away screaming, and for ever after they will spread the word that this community is incompetent.
I believe that it has to go one way or the other - either Oracle is supported fully by everyone or it goes. Since the community has made it abundantly clear that not everyone is willing to support Oracle, and no-one in a leadership position is going to force the issue, then we seem to have only one option left.