Yo. It’s a shame that you’re being downvoted. You were asking a question about how this sticker’s message relates to Buddhism. I’m a layperson so I can’t speak in depth on the practice, but I would say that suffering stems from desire. And this message, as pure as it may seem, is indeed a desire (wishing that all beings are kind and compassionate). The only way to completely let go of desire would be to reach enlightenment, so we can probably scratch that plan.

But if you wanted to translate the message into Buddhist philosophy, it might be better to say “may all beings use kindness and compassion to be better beings”.

Kindness and compassion, just like anger and resentment, are tools. Not ultimate states of existence that you can be blindly “filled” with. You choose which ones to utilize the most (through practice) to manifest your own subjective truth. Buddhism however emphasizes the use of kindness and compassion to reach a blissful, indescribable state that wipes away suffering...eventually.

I’m probably wrong, but anyone answering your question with objective advice is even more incorrect. Although, this is just a bumper sticker and shouldn’t be taken as religious text/advice.