Big Sur Lag Fix??

Happening to me, very tempting to go back using Time Machine

I have the same problem with my 

MacBook Pro (16-inch, 2019) 
2,6 GHz Intel Core i7 6 core
16 GB 2667 MHz DDR4
AMD Radeon Pro 5300M (Intel UHD Graphics 630)

This is a huge problem for my productivity. A great Mac ruined after the installation of bigsur. 
I tried to reset PRAM and SMC, but the problem is here!!!

Please help me...

I am having the same issue with a Max spec 2019 16 inch macbookpro. I hope there is a fix soon. Simple Word processing is unusable and delayed.

Same issue here....

After Big Sur update the machine is extremely slow on performing basic tasks, such as log into profile, change profiles, and anything which uses graphic card, such as simple gaming in windowed mode and low res, which with Catalina did not happen at all.

Noticed some screen "blanking" on loading from boot:
The load screen background and the screen itself go black and then reappear.

Noticed on switch between existing users, that the computer displays the load icon on the mouse for a few second after showing the new login screen for the user, and after it disappears it takes up to 5 seconds before you are allowed to write the password on the field, almost a "mini lockup" or lagging.

Opening files via Browser such as Safari takes much longer than usual, also data download start seems slower even for small files such as a PDF of 238Kb.

Even text scrolling via cursor keys is slower.

Machine Specifications:

MacBook Pro (Retina, 15-inch, Mid 2015)
CPU: 2,5 GHz Quad-Core Intel Core i7
RAM: 16 GB 1600 MHz DDR3
GRAPHICS: Intel Iris Pro 1536 MB
HDD: APPEL SSD SM0512G (free space in HDD 353 GB) - APFS file system

Is there a chance to roll back to Catalina? Big Sur is definitely so very disappointing that I wish I hadn't updated until it was stable enough.

Never had any latency or lag issues with Catalina, or Mojave for instance...

same here 2017 macbook pro NTB.
MacOs BIG SUR became a BIG SORE!

I also have this issue with a 2019 Mac Pro with the 16-Core variant. This is obviously not a hardware issue, and happens every time I open a project in Xcode or it does "Indexing"

check out this thread: https://developer.apple.com/forums/thread/666661
It's clearly a big flaw in Big Sur.
I'm using a MacBook Pro (Retina, 15-inch, Mid 2015), worked splendidly on 10.14
It now feels like a cheap supermarket promotion with a version of Windows that is far too heavy for it....
I hope Apple will see the thread growing and patch this huge issue.

When I initially updated my MacBook Air 6,1 I found the same problem. I cleared the harddisk completely and did a reinstall of Big Sur with internet recovery. All of the Lag is gone and the system is quite responsive even with 4 Meg of ram. Replied here just as an information point for you. seemed to fix every single lag problem including airplay over my tv.

I am having the same problem, MacBook Pro (Retina, 15-inch, Mid 2015 2.8 GHz Quad-Core Intel Core i7, 16 GB 1600 MHz DDR3), LAAAAGGG big time.
I run adobe creative cloud, and mouse is jumping around and get spinning beach ball of death all the time, have to restart often.

Any solutions yet?

I notice BigSur is having issue when adjusting volume bar (mute, volume down, volume up) after macos is restarted for sometimes (after a day? ) It is very laggy when adjusting volume and cause the whole bigsur system to lag and freeze.

Also having an issue on a 2019 Macbook Pro, 1.4 Ghz i5, 8 gigs RAM. Unfortunately, going back with time machine isn't an option. Has there been any developments on this? Watching videos, working, pretty much everything I do has become excruciating.

My experience is that the lag depends on the external display's resolution a lot. Also it does matter, if you use the native resolution of your external screen, or if you can set integer multiply of the original native resolution to your external display or not. For example for me it's better if I choose 3200x1800 instead 3360x1890, I have 3840x2160 native resolution.

In the display settings if you press Option during clicking custom resolutions you will see other options, you can also set your resfresh frequency, make sure you can set 60Hz! This needs higher quality cables as well, take of this.

Despite I tried use the best cable etc. I still experience more laggy experience which is changed in Big Sur. I think the VGA drivers are rewritten and it's a piece of shit right now, needs to be optimized!

I haven't tried the new Beta OS yet, I hope that will change this very ****** experience.