Minimize Dirichlet eigenvalues for Laplace operator

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Good time of day. Can you help me please?

I try to solve the following task for the Laplace operator for bounded domain $\Omega \subset R^2$ with Dirichlet eigenvalues.

I know that that the disc minimizes the first Dirichlet eigenvalue $\lambda_1(\Omega)$ among all planar domains of the same area. Also I know that the disjoint union of two discs of the same radius minimizes $\lambda_2(\Omega)$ among all planar domains of the same area (Faber-Krahn theorem).

I try to understand why that the disjoint union of $n$ discs of the same radius cannot minimize Dirichlet eigenvalues $\lambda_n(\Omega)$ for all $n$. I have found in this article (https://arxiv.org/abs/0808.2968v1) that this contradicts Weyl's law but I don't understand why it contradicts. Please help me and explain it in more detail.

Thank you