Have you reached your end point with this addictive hobby?

Yes, but I still read the ads. Nothing new about that I have any interest in except for recordings (CDs). If I get really (!) bored, I do have lots of good old stuff about that I can play with.

I have always aimed at upgrading "a level". Reaching as high as I could and then over the next couple years upgrading all components to that level. This is the active upgrade time. Then I optimize for a year (positioning, cables, vibration control, etc.) while enjoying the music. Then I just enjoy the music. I have found that in this way, each component is a major upgrade, and once completed, synergy has kicked in and elevated it performance to a new degree. I increasingly spend more time listening to music. So, at least for me the desire to upgrade goes away for five to ten years. During that time, I still read Stereophile and The Absolute Sound, keeping track of advancements... but the desire to upgrade is completely absent. Until the years have gone by, I have recovered finanicially and I can start thinking about the next level. Which for me always involves a 2x investment or more, as that will net a huge jump in performance.

I'm pretty much done.  Have a decent mid level system.  Added a streamer to make things easier.  with a 4 watt int amp I'm tempted to replace my speakers but they sound good and I don't listen to loud levels anymore.  Almost always buy used.

Yep, completely done as of summer of 2024...no more gear. It actually worked out well because the cost of new and used gear (and shipping) is now officially, certifiably insane.

I was going to chime in, but @grinnell described my situation perfectly. At this point, I’ll buy something only if something I have breaks, and even then I’ll likely buy used.