At the top of the line is it really all that different?

Many if not most reviewers give glowing reports because they get the gear for free and either then buy it at a much reduced cost or simply like having all the latest stuff to play around with for a while. If a reviewer gave consistent negative reviews, manufacturers would stop providing them stuff to review, for obvious reasons. To answer your question, there isn't very much difference that can be objectively identified in any of it regardless of the cost and zero difference with things like interconnects or speaker wire.

I'd like to add another dimension to the satisfaction matrix of audiophila (?): circumstances of purchase.  Seven years ago I was a regular visitor to the Seattle CL for audio although I lived on the east side of the state.  For weeks myself and the rest blew right past a Time Frame post.  Slightly blurry, 300 dollars.  Just another pair of old TF400 or such.  Finally one day I took a closer look.  TF2000?

A quick google search had my trembling fingers trying to dial.  A brief conversation and a PP deposit and the pair were mine.

Fast forward to now.  I have loved the sonic magic of these hammers the WHOLE time.  Are there better speakers on paper?  Sure.  I find the imaging and tall soundstage to be all I need.  Effortlessly dives into the deep end.  And I still smile when I think of how I got them.

I power them with a Proceed HPA 2 via a Lexicon MC-8 Controller in analog 2 channel bypass mode.  Nothing but praise for both online and the three play so well together!  Both components bought for much less than original price.  Older gear hold its own against the new at a significant discount.  The SF Bay Area CL is loaded with bargains of gear flippers like the folks in here, thank you!

I recently bought a pair of Von Schweikert VR4 Gen2 for 1000.  Backups for when something goes south in sn 446 or 447.  No one can say it is not a spectacularly great speaker.  Yet my 2000s remain.  Not one to waste such great speakers I took them to my local cannabis dispensary.  I brought a little Audionics CC-2 amp I picked up for 60.  Ground breaking design in it's time, made in Beaverton OR.  A cheap but good Rockville PPA53 BT capable pre and my owner friends, employees and customers get a taste of the high end.  A LOT of compliments by some knowledgeable customers.

In the end does your music make you smile?  Time to quit climbing and enjoy the view... 

Good question. In my experience as you go up the line and up in price the sound quality often improves but there’s a point of diminishing returns. Just about everyone has a budget. I suggest trying the best equipment you can afford. work with a dealer or manufacturer that will let you buy, try in your listening room and return if necessary. The challenges once you have a system that sounds good and fits your budget is FOMO and new equipment constantly coming out. I find tweaking my system if a fun part of the hobby. Having different systems as you do allows you to do that more easily. Most importantly as Hans says, enjoy the music.

Some very thoughtful answers here, but imho I think you likely already know the answer to your question.  You’ve listened to some outstanding and expensive gear and in your room and to your ears you hear very little difference.  I say trust your ears.  I realize there are levels above even the $50k component cost and some like chasing that last small percentage difference, but it seems like even though you can identify the modest change it may not be worth it to you.  I entertain upgrading sometimes and go listen to components at the next level from where I am and usually end up at they sound wonderful but not enough to justify the 3-4x price over what I already have.  I always come back to that I really love my modest system and the way it sounds.  I know I’m leaving some things on the table but I guess I’ve just decided to enjoy it and the music for now.