That's Baybayin. It's an old Tagalog script that isn't really used anymore outside of aesthetic purposes. It's not commonly taught and used in schools for example. Even I couldn't read this without a guide. There are some efforts to try to revive it though.
Tagalog is usually written with the English alphabet. Like this: Magandang gabi po. Google Translate works.
Hrm, I guess.. But it's the 23rd most spoken language globally.. Nearly 90 million speakers, and I don't think I've even seen the alphabet until now. I feel like I've seen lots of posts from less populous languages..
Same supply and demand issue: how many Baybayin keyboards do you see in the making&circulation, virtual or physical?
Thus the US&Spanish alphabet was forced.