Can one ever be "done" in this hobby?

Depends on how far the technology can and will go. I think 🤔 as a headphone and loud speaker user you can stay put for quite a while if everything in your soundchain has some degree of performing on an elite level. 

The audio world really shifts every 7 to 10 years in terms of huge leaps in audio tech performance and quality. 

So if it's a hobby that you enjoy, why would anyone want to be done?  Honestly, I have no desire to "be done".  It's exploration and new experiences.

I desire to be “done” because audio is a means to an end. The end is an appreciation of the music. 

I have got my system up to where, while I know it’s not likely the best, it’s at least 90% there. 

I have 5,800 LPs. It will take me years to go through all of them just on what I currently have.

After a while, like whats the point of fussing with it? Records having the wide range of engineering quality that they do, there’s enuf fussing around with each LP as it is. 

There’s a famous quote, something about repeating the same things over and over again and getting the same results. Was it Einstein? 😛

I believe it was his cousin, Alfred E Neuman.