From what I remember, the first point here is that excited states tend to not be stable. With there still being an open energetic “spot” it was promoted from, the favorable thing to happen here is for the excitation energy to be released/converted and for the electron to fall back into its ground state. Often this is how fluorescence and emission works from materials–fluorescent dyes are essentially just molecules that are efficient at being excited in this way, then when falling back to the ground state they release light to get back down, often in the scale of nanoseconds.
Second point: that excited state indeed can often last incredibly short periods of times.
Third: under extreme conditions you might be able to force an atypical bonding state to be comparatively more stable, but it would be the exception and not the rule. Still, it happens, so some rules we have for the “bonding” orbitals and the like aren’t as simple or inflexible as sometimes first introduced. For example, CH5, PCl5, and SF6.
Fourth: aside from the above points, there’s also the bit of charge and electronegativity. The electrons of the atom can be moved around, removed, donated, and so on much more readily than the protons and neutrons of the atom core. And, this core influences the electronegativity / affinity towards pulling electrons in. Exciting electrons won’t change that part, and that part is what essentially defines much of the electron orbital energy landscape–which in turn informs bond and interaction stability.
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