Logitech K350 wireless keyboard input lag

So, I have a problem with my Logitech K350 wireless keyboard. It was working fine for years, then recently I started to regularly get input lag, sometimes it's brief, sometimes the keyboard is unresponsive for seconds and lasts for a while. It is very annoying and definitely seems to be a Windows 11 issue, but couldn't figure out what and not to bash Windows, but -frankly- this OS doesn't give any easy to use tools to provide meaningful troubleshooting.

Before I am asked / pointed to certain areas, let me tackle the obvious questions:

Your battery is running out.
No, it doesn't (tried with different batteries, rechargeable, non-rechargeable, etc).

Something is blocking the signal.

No, it doesn't. Nothing changed in the room layout, ~3 meters, no items between the keyboard and the USB receiver.

Your keyboard is faulty.

That's what I thought as well, after all it was like ~5 years old. Bought a new one and it shows the same symptoms too.

It is not a Windows 11 issue.

Maybe, but I don't think so. First and foremost, it was and is working perfectly with Windows 10. Then, it was working perfectly fine under Windows 11 for a few months, then roughly 2-3 months ago the problem started. First the lag was brief, and became more severe lately.

Use Windows 10 then.

That would be great, especially that Win11 is... I don't like it, let's put it that way. However, my laptop is not Windows 10 compatible, so no chipset driver, no fan control, etc.

Did you try to upgrade firmware / install drivers?

Yes and yes. Technically, K350 doesn't have downloadable drivers, rather than a Setpoint named logitech weird bloatware, but yes, I installed it and it doesn't show any issues.

Did you try to remove the device and add again?

Yes, and I also did a full Windows 11 reinstall. Same problem persists.

Other, misc. things which check out:

• Logitech driver is loaded according to device manager and the latest logitech drivers are installed (tried manually updating, but it was the latest already).
• Windows troubleshooter didn't report any problems (not like it ever did any good since Win 3.1, but still, gave it a shot and no dice).
• Power mode is best performance and USB battery saver is off.
• Windows has the latest updates.
• In the device manager the box to turn the device off to save power is unchecked, so no lead here.

My two cents is that something may be off with Win11's USB power management. Since usually the problem happens when I don't use the keyboard for a short time (at least a minute or so) and/or when Windows is idle for a while and I try to use the keyboard. However, while in Windows 10 you could disable USB power management, I didn't find similar option in Win11 in battery management, only USB battery saver.

All tips are appreciated and thanks in advance!