Windows 10 users will likely be receiving a new Windows Update (KB5053643) as part of the Patch Tuesday rollout, but this “update” is more likely to be seen as a downgrade – when the update applies, the calendar flyout on the taskbar will no longer show the full clock in seconds, which means there is no way of finding accurate time down to the second, unless you rely on third-party solutions.
Windows 10 Clock Gets Nerfed

Despite this change, there’s unofficial ways of saving the clock – one of the more extreme options involve blocking this particular update from applying on your system, but it’s not recommended unless you know what you’re doing. Alternatively, third-party tools like 7+ Taskbar Tweaker (which I personally use) can enable full clock display on the taskbar (though it won’t change the flyout UI), as long as you don’t mind slightly higher CPU usage, which may slightly impact battery life if you’re using laptops.
It’s a very confusing change, to say the least. Microsoft’s reasoning for this change is to reduce CPU usage, as showing clock down to the second in GUIs will prevent the processor from entering low-power states due to the constant need to update the clock every second. Even then, this didn’t stop the company from adding the seconds to Windows 11 as an option through Settings for users that need it (and it even reminds the user of increased CPU usage if you enable the option).
This feature might be a long time coming given that it was discovered earlier this January; with just a few months left on the clock, the now nearing 10-years-old operating system will stop receiving updates altogether, so don’t expect the software giant to reverse this decision, or at the very least, make this an option instead of a permanent change (like in Windows 11).
Source: Windows Latest
Pokdepinion: At this point I expect nothing good from Microsoft these days.