I agree with Kaindub, a rule made just by the Committee is not the same as a by-law, and doesn’t have the same status. So for example you couldn’t apply to NCAT for a fine for breach of a rule.
The comparison with regulations which form part of the law isn’t correct.
The Act provides for the owners corporation making by-laws, it doesn’t provide for the Committee making rules as a subset. The enforceability of any by-law or rule comes from the Act.