Just AM/PM will reduce a lot of such issue. No need pagi/petang, morning and night.
So why airlines don’t want to use AM/PM? I believe AM/PM is well understood internationally.

Just convert the time when printing the boarding pass. It’s not a big software change. Compared to the time/money wasted due to misinterpreting of the time. 0.1pct is still a lot. The system can be used for > 10 years before a major upgrade. In those 10 years, how many passengers are saved from misinterpretation of the time.

Of course we can always argue it’s customer’s fault. But it seems to be something worth to change.

I believe most of them either overlooked or lack of knowledge.
You never overlooked something in your life?

Why not cater to them if there is significant people faced this problem?

I agree 24h less mistake.
But in our daily life we use am/pm. We are not in the military. Why not use something that we are familiar with?
Do you convert to AM/PM in your mind when you see 24h format?