It depends on what you mean by 'beginner'.
I think in anything like this it's always best to speak from a personal perspective, and in that context you are not a beginner. If a beginner wants to apply, let them, if they dont get in, move on... There is no requirement for a league to be everything for everyone, where a league tries to attain a certain goal and is clear about what it is trying to achieve then I say good on any league admin who limits the field to people who are with the program and understand what the league is about.
To put it into context of STCC, I have had more than 1 driver enter STCC races who didn't get what it was all about. Why should I spend most of a month editing a race together only for some idiot to spoil the whole thing, and spend most of my time editing out the impact of said idiot from the footage...