というものだ is a fairly strong expression in Japanese that indicates that the speaker has the impression that (A) is the way it is, based on their objective judgment. This is usually translated as 'my impression of (A) is that'. However, the more literal translation is closer to '(A) is just a thing that'. This emphasizes that the speaker has high certainty that what they are saying (based on their experience) is the true nature of (A) in most cases.
というものだ is constructed of という, the noun 物（もの） 'thing', and だ. It will be seen at the end of phrases that the speaker or writer is making a judgment about.
何（なに）があってもお互（たが）い助（たす）け合（あ）うのが友達（ともだち）というものだ。
Helping each other no matter what is just what friends do.
先輩（せんぱい）が着（つ）く10分（ぷん）前（まえ）に着（つ）く。それがマナーというものだ。
Arriving 10 minutes before your senpai arrives. That is just manners.
どんなに疲（つか）れていても諦（あきら）めない。それがアスリートというものだ。
Not giving up no matter how tired you are. That is my impression of an athlete.
As this grammar pattern is quite direct, it is often used when criticizing something. However, this is not always the case, so will need to be judged based on context.
Caution - In casual conversation, という may be shortened simply to って, without any change in meaning.