Can one ever be "done" in this hobby?

Power handling and efficiency aren't necessarily related...like saying, "it's heavy, but it's green." I likely use a couple of watts to get my 99db speakers filling my ears and the room, and the peak capability of 'em is 400 watts. You can have a very efficient single 5" speaker that will explode from a steady 20 watts, and an inefficient speaker that will do 300 watts of uncompressed kick drum all day.

To the original post.

I actually think you can be done. But only if you beleive there are actually two different hobbies here. The audio hobby and the music hobby. I have to say I am mostly on the audio gear side. So as long as I focus on sound I will always be searching for something different and or better. That's why I constantly rotate speakers. I really like my power and pre amp so only on ocasion will I switch to my vintage Marantz, Sansui etc receivers. I have 3 TT's and switch them on ocasion as well. 

People who focus mainly on the music can be done with the Audio gear side. What is most important to them is the music. On what it is playing is not the most important thing, just that it is playing. Clearly evidenced by the mobile players now in millions of peoples hands. They are way better than what they used to be but not what most of on here would call great sound. Sure, "music people" if financially able,  will search for a system that suits their needs but it is still all about the music. 
So I would say in reality there is actually two different hobbies here joined by one commonality, the music.

I think I am going to put out a seperate post on the topic. Is this actually 2 different hobbies. 

I had a set for almost 20 years and last year changed all the components .

Me a couple of days ago: "I'm pretty much done. And happy."

Then I saw a glowing review of the very inexpensive Schiit Mani. Now I want one. I'm a sucker for something that is reasonably cheap and reasonably good.

So the answer to the original question: No. Not quite.

But, I also agree with the post above about music vs equipment. In truth I'm pretty close to be done with equipment. There may be minor purchased here and there. But on the music side, no I'll never be done. Always looking to new stuff. Always open to better recordings of stuff I already have.

"Can you determine which exotic car by the sound of this exhaust?
https://www.youtube.com/watch?v=n2QIlwyO2wk"

The sound at the end of Queen song "I'm in love with my car" is Alfa Romeo.