Why is my Win 11 slower than Win 10?

I can only support SlantCut's report about a desastrous performance of Windows 11 when compared to Windows 10.

After a long consideration and for the dawning end-of-use term of Windows 10 in October 25, I decided to switch from Windows 10 Professional 64bit to Windows 11 professional 64bit early enough in Oct 2024. After a thorough testing since, I must say this was the worst decision I could take.

Contrary to what the other replies state, I would not consider my hardware out-dated: I have a Lenovo X390 Laptop at an Intel i7 8565U CPU @ 1.80GHz   1.99 GHz with 16GB RAM on board, a 2TB SSD drive, so strong enough according to Windows 11 specifications to support this OS. I have an AVAST PREMIUM SECURITY suite running for my security. I have all drivers updated to the newest versions, and use AVAST DRIVER UPDATER to identify outdated drivers.

Fact is, though, that since having switched to Windows 11, I am constantly running on short memory, the number of programs / "apps" running in the background has dramatically increased without any extra benefits for me as a user. 

I am a user who is used to keep a lot of programs running in parallel so that I can quickly jump between them by "alt-tab". This usage mode also helps me not to forget tasks I had to interrupt in between. In addition, to be able to seamlessly continue my work I only restart my OS once a week or so, and in between only let the OS fall asleep. This worked perfectly with Windows 10, but has gone dramatically wrong with Windows 11. This may not be the recommended usage, but it was my workflow which was working without any problems for me with Windows 10. And instead of improving on this with a new OS, Windows 11 has dramatically deteriorated my workfow.

Windows explorer is failing, once I have more than 6 instances with different file paths open in parallel; Windows 11 kills applications without prior notice, which is particularly bad in case of my KeePassXC password safe demon running in the background. Acrobat reader is only working in slow-motion, I can no longer smoothly and gradually change the displayed size. It takes ~5 seconds to switch from one application to the next one via alt-tab (and < 0.1 second in Windows 10). Switching between WLANs is a nightmare (in comparison with Windows 10) it takes ~ 2 minutes (and ~ 30 seconds with Windows 10) and it takes ~ 5 minutes after arriving at a new place with a new WLAN to start up a new teams session compared to ~ 1 minute with Windows 10. With Windows 11 Firefox eats up ~1.5 GB, and Thunderbird the same while with Windows 10 it only needed 700MB respectively.

So Microsoft should be honest and only recommend Windows 11 as is for machines with >= 64 GB RAM and 3GHz processors...  Before Microsoft is really doing something about this, I can only recommend to stay with Windows 10 as long as possible. 

I would not consider myself an IT expert but still close enough to to be a voice that should be heard. I am a professor for applied statistics at Oldenburg university, so do have professional skills to be believable when judging such a system.

Prof. Dr. Peter Ruckdeschel