The use of the word "weakness" is purely subjective. Something that may be considered a weakness in some circumstances may be regarded as a strength in others. For example, argon is inert and so does not form compounds. A weakness? But that same property makes it extremely useful for the storage of highly reactive elements. A strength!

Argon comprises almost 1% of the air. It is obtained by fractional distillation of liquid air.

Helium accounts for around 8% of the volume of all matter (baryonic particles) in the universe.

Yes.

It is very inert. However, under extreme conditions it can be made to react - to form compounds. Argon hydride was detected in the Crab Nebula in 2010.

They are all gases at normal temperature and pressure.

Usually nothing: it is inert.

Because of its inert nature, it is used to provide an inert atmosphere in industrial processes involving very high temperatures. This protects the material being processed reacting with any of the surrounding matter. Other noble gases could also be used but Argon is cheaper to manufacture.

It does not have any superpowers.

Yes it's a magenta color

Silicon is a covalent macromolecule. Argon, on the other hand, only has weak Van der Waal's force.

It is one of the noble gases.

Slightly less than 1% of the air that you breathe in.

argon is a noble gas

Discharge tubes with argon produce a violet light.