I remember we definitely hesitated about point 4 and also considered going with "only one system", but depending on what you consider "a system", this seemed very minimalistic to the point of becoming almost counterproductive. Also, we thought the idea that you might let someone join the project, just so you can “take advantage of yet another system”, was kind of hilarious.
But that's a fair point, yeah.
Your comment about radicality is interesting, although I don't think any of the example you gave is, in itself, more "radical" or "extremist" than our manifesto. But, really, what was our idea in the first place is : a very tangible, actionable set of rules about how to make games a certain way (inspired by the Dogme 95). Being queer perverts, "killing the capitalist in your head", etc. is definitely equally interesting, and I'm glad such manifesto exist, but it does not really give the reader an actual set of rules to try to follow, which is precisely what we thought was fun to imagine.
We believe the set of restrictions we created can be inspiring and fun to try, but following a set of hard-coded rules is, by design, a bit silly.
Our hope was that, by following these rules, a person would be able to make a game that they would not have created had they not followed them.