Why is Windows 10 Bluetooth so so so bad ?

I've yet to come across a more drastic failure by a technology company than this. Period. Beyond frustrating.

Same, flawless on a handful of devices but gives me CONSTANT trouble on my PC. Microsoft sucks and will likely never fix this.

Typical MS Fanboy bull. 

the THEORY. The FLOWCHART, of windows 10 bluetooth UX is drop dead simple.

So simple in fact that they never managed to get it to work in most cases.

Again, let me walk you through the DROP DEAD SIMPLE steps of troubleshooting!

Isolate the problem. This requires you to have a few devices to shuffle things around. So we isolate the problem by trying different combinations of devices, adapters, operating systems, etc. In my own house I have 2 windows 10 PCs, Samsung Galaxy S6 phone, Samsung Galaxy Tab A, all of these devices have their own built-in bluetooth adapters. I also have an ASUS BT-400 USB adapter. I have a skullcandy Sesh BT earbud set, and a SENSO bluetooth headset. This gives me pretty much everything I need to test.

Connect SENSO to PC2 via Onboard = Failure - problem could be with SENSO, Onboard adapter, PC, or Windows.

Connect SENSO to PC2 via ASUS = Failure - problem is unlikely to be with the onboard adapter. Could be with SENSO, PC, or Windows.

Connect SENSO to PC1 via ASUS = Failure - Problem is unlikely to be PC, onboard, or asus adapter. Could be with SENSO or Windows.

Connect SENSO to S6 via onboard = Success - crystal clear audio. Problem is unlikely to be SENSO. Could be Windows.

Connect SESH to PC2 via Onboard = Failure. Problem could be SESH or PC2.

Connect SESH to PC1 via ASUS = Failure. Problem could be SESH or PC1 or ASUS adapter.

Connect SESH to PC2 via ASUS = Failure. Problem could be SESH or PC2, unlikely asus adapter (since problem already exists with the same hardware but an onboard adapter)

Connect SESH to S6 via onboard = Success! Crystal clear audio! Rules out the problem being Sesh

See how this works? We rule out the sesh by getting crystal clear audio in another device. We rule out the adapter because the problem persists even with other adapters. We rule out the tower's hardware by swapping tower hardwares. And a previous user here has even used all the exact same hardware and switched only the operating system from Windows to linux. With EVERY ELEMENT OF HARDWARE COMPLETELY IDENTICAL windows fails the connection and Linux operates seamlessly. 

This is science.

"Well mine works fine."

This is an anecdote. 

Troubleshooting is not always about -you- until you have had the problem, and solved it, your input is very rarely helpful, and only serves to insult, degrade, and cover up an actual problem that many people are having. Replies like yours make people who have legitimate problems NOT SEEK HELP. 

So with all due respect, which is none, shut your hole until you do some actual research beyond "well I never had the problem so you must be an idiot."

TLDR; Yeah me too, and I really need a solution that doesn't involve windows being junked.

I am about ready to see if bluetooth is better on linux. I have NEVER gotten bluetooth to work reliably with window 10. And that's with two differnt devices, two differnt bluetooth dongles, and two different computers. The OS is the only common denominator. 

I've just done that and it is day and night.  I couldn't believe that natively on Windows my headphone range was 3x shorter than the one I got on Ubuntu(via VIRTUALBOX!!!!!!). The connection was much more stable and compared to Win drivers(Intel device), after returning from poor reception zone, the Bluetooth remained to play well with good audio quality. On Windows it becomes terrible and you have to reconnect to get to the default quality levels.

And don't get me started about the mic. It is hard to believe how bad is the Bluetooth management on Win.

Even on mobile phones, it is working around 100x better.

I'm so sick and tired of Windows that I'm finally thinking about switching to Mac

I am about ready to see if bluetooth is better on linux.

On the Arch kernel at least, the bluetooth audio works really well with pulseaudio. The computer scans every few seconds for paired devices, so as long as you don't have a bazillion of them, you should be good.