The joke is on the aliens.
Voyager's batteries are going to run out real soon, and then they won't be able to reprogram anything, it'll be just a huge paperweight.
A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.
The joke is on the aliens.
Voyager's batteries are going to run out real soon, and then they won't be able to reprogram anything, it'll be just a huge paperweight.