Imagine being 15 minutes late to the heat death of the universe. Unacceptable.

I mean but this should save me some hassle from my current clock that I need to adjust every 10 billion years.

The Germans will be furious

Oh shit I missed the sun explosion!

... or one second back, that's the problem.

Remindme! 30 billion years

Just give me a little bit of time, I got this. You’re gonna see!

Yes, of course.

In clocks like this, the "set time" is often irrelevant. It's more important to know exactly how much time has passed since the last time the clock was "checked." If you're running a radio transmitter at 6ghz, that's 6 billion cycles per second. If you synch your transmitter to your clock once per second, it had better be accurate to the billionth of a second.

The other atomic clocks that are averaged to give us our ground truth for time.

Standard seconds are defined based on measurable properties of a cesium atom. The historical definition of 1/86400th of a day doesn't work for science if the duration is inconsistent.

For example the statement:

Earth's Days Are Getting 2 seconds Longer Every 100,000 Years

becomes self-referencing and loses all meaning without some other reference point.

This is time relative to earth, and the actual passage of time in the universe that we aim to measure doesn't care about the Earth's rotation.