That first one was so heartbreaking. Don't adopt animals if you're not going to take care of them. You know how people say "All children deserve parents but not all parents deserve children?" It's the same for domestic animals.
I don’t think it’s Hitogata. 1. This specific PSA is from 2004, & the original Hitogata thread is from that same year, but the poster there claimed that they saw it as a child presumably in the late 1980s or early 1990s. 2. This PSA is live action, & Hitogata accounts nearly always say that that one is animated. 3. There’s no flashing, & only one person is dressed in white. 4. AC Japan has denied making Hitogata multiple times
I don't know either, but Hiragana is mostly considered a women's writing style. Men mostly write in Kanji. So maybe he is writing in Hiragana to sound softer and more emotional because he's sad about his friend dying. Maybe?