I strongly advise against this because your mileage will vary. Some random forum poster’s experiences are anecdotes, not data. They’re not representative of what’s out there.
Try it out yourself for a while, and if you do run into serious issues you didn’t have in Sierra, downgrade.
Or, just for fun -
You could ponder how it is that Apple can't effectively streamline an OS that's restricted to running on hardware they also produce. No... don't do that - why... that would be... heresy?
If you're also running devices that weren't created by Apple specifically to run with their OS - which I'm not doing - heck, I even bothered to remove an SD card just to make extry special certain - but hey...
Then you could run a clean install of Apple's OS on Apple's machine with absolutely no devices attached - at which point...
Yep.
But hey - don't do that? Or do do that? As long as you don't whine and agree with us that... do what exactly now?
I strongly advise against this because your mileage will vary. Some random forum poster’s experiences are anecdotes, not data. They’re not representative of what’s out there.
Some random forum poster's experiences running a clean install of Mac OS on an Apple device are anecdotes, not data. NOT DATA!!!!!
Why, Apple can not POSSIBLY be expected to test their OS on EVERY... Oh, COME ON!!!! That'd take... like half a day maybe if one dude had to do it all by himself, in a shed with a generator? Oh COME ON!!! Who has that kinda time?
So here's what you do -
You claim that High Sierra runs very well - okay, well it runs somewhat passable, well certainly not horrible - for YOU and that the person complaining whines too much.
And, when they limit their complaint to a startup lag JUST to mock you for how FAR you'll actually go to apologize for your most favoritest corporation ever...
Uhm... it must be their specific machine that's faulty? They MUST run further tests! Apple doesn't have those kinda resources and time and billions of dollars and... STUFF!
So what if Sierra alternately runs just fine with no complaints? That's NOT THE POINT! Stop WHINING about High Sierra, you... you... WHINER who hates everything Apple, except you don't, but you dare to post that High Sierra is... HORRIBLE? HORRIBLE!?! Why, how RIDICULUS... what, are you just trying to make a POINT or something?
What, did you intend to draw us out just to mock us? I don't think you're taking this seriously AT ALL! You keep cracking lame jokes...
See, you just proved you have NO POINT! We don't CARE about the stupid startup lag. WHO CARES!?! NOBODY!!!! That's WHO! NOBODY CARES!!!! GOD WE HATE YOU!!!!
Now, back to our safe space...
Oh, what new Animojis do we have to look forward to this week? Yes - it's VERY important GROUND BREAKING stuff and stuffs! Apple only has so much time...
SHUT UP!!! You are just insufferable with this startup delay on your top of the line best you can get most powerful ever when you bought it 3 year old* MacBook Pro! IDIOT!!!!
Okay, well we can still hate on the guy with the 10 year old one. WHAT AN IDIOT!!!! You're lucky Apple even allows... INGRATE!!!!
Wow... just... wow?
*FOUR? Late 2013, OS introduced in 2017. Okay, so you bought it in 2014? LOSER!!!! Your fault for buying such an old crappy machine. Should have waited for the touchbar magical touchy bars. Why wouldn't you want that? JEALOUS!!! IDIOT!!!!