What does big Omega imply about big O? And how does $f(n)=\Omega(n)$ imply cannot be bounded by a constant?

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I'm trying to figure out the implications of $\Omega$ in asymptotic analysis. Let's say I have a function $f(n)=\Omega(n)$. From my understanding, and Asymptotic analysis: difference between big O and big Omega limits?

this implies the following:

$\exists c>0$, such that $\exists n_0 $ s.t. $\forall n \ge n_0, \,\, f(n) \ge cn$

In some literature, I've heard this described as "f(n) cannot be bounded by a constant". I'd like to know why that is the case. To me $f(n)=\Omega(n)$ seems to imply the following:

$\nexists c >0$, such that $\exists n_0 $ s.t. $\forall n \ge n_0, \,\, f(n) < cn$.

...which to me means its performance cannot be bounded by a linear function of $n$. i.e. $O(n) < f(n)$. How does this imply $f(n)$ cannot be bounded by a constant? Can't we say something stronger?