Meaning of ものなんだろう in this sentence


[![enter image description
here](https://i.stack.imgur.com/TLY5F.png)](https://i.stack.imgur.com/TLY5F.png)

What function does the もの server in this sentence? Wouldn't it work with just
なんだろう?

He should be saying that the people who followed the idol group to the very
beginning are even more emotional.

But what ものなんだろう adds here?




This sentence has 感動物【かんどうもの】, which is a fixed compound noun that refers to a
work/event that moves/inspires/impresses people. なんだろう is simply
explanatory-(な)のだ followed by だろう.

感動物 is used like this:

  * この小説は感動物ですよ。  
This novel is moving!

  * 感動物の映画  
heart-touching movie

  * 友人の結婚式に行ってきました。感動物でした！  
I went to the wedding of my friend. I was moved/impressed!

> 古参の方たち(に)はもっと感動ものなんだろうな。  
>  (It) should be even more impressive to old fans.

