Proving the well ordering principle starting from the axiom of completeness. Is this topological proof valid?

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While reading this SE thread, I saw in the comments someone say "the proof [that the completeness axiom implies the well ordering principle] will take some work".

However, this other thread shows that by using the definition of infimum we can establish the above-mentioned result rather easily.

An even easier way of proving the result would be to say:

Let $A\subseteq \mathbb N$ be non-empty. Then, as $A\subseteq \mathbb R$ and $0\le x, \forall x\in A$, the completeness axiom gives us the existence of $s=\inf A$. Then, by topological arguments one can show that $\mathbb N$ has no limit points hence is closed. Therefore, $s\in A$ and $A$ has a minimum.

Is this easier way of proving the result valid ?

Thanks in advance

PS: the topological arguments are that if $p$ doesn't coincide with the natural numbers, $p$ can't be a limit point (there is void around it). And if $p$ coincide with one natural number, it can't be a limit point either (since the definition of limit point excludes the point of consideration).