It wasn't shimmering, but the "hey I'm your computer and this is what I'm doing, oh watch, now I'm doing this" paradigm, was popular in loading screens, installers, and the explicitly personal / anthropomorphized language was on the rise for a long time.

Starting with addressing users personally instead of using neutral language like with labels in physical tools.

Also the "drawing attention" part I think mimics chat interfaces, e.g. Windows installer since Win 8.

But still no shimmering text there. Indeed interesting who started to come up with this.

Other similar, earlier trends I found:

iOS Slide-to-Unlock text!

And the shimmering of loading skeletons is also similar, although they're not text.