I think we've all had friends who were co-workers, or just friends from childhood, or friends who were friends, who ghosted us.
I've been "ghosted" by a few friends, and in one case I understood (her overly possessive boyfriend didn't like how we remained platonic friends since we were 11). The other, it wasn't a long term friendship, but we were close. She just stopped communicating with me, and I never found out from her why. I would message her, but nothing. I chalked it up to life happening, and didn't take it personally.
She ended up passing away suddenly a few years back, and it came as a surprise to me and everyone. She had found a new boyfriend, and they were getting close and probably just didn't have time to message me (we were completely platonic).
But if I found out that a friend of mine (I have 2 really good friends) were dying, and I was able to visit them? I would. I also would text them on a regular basis (I actually text them both of my friends on a very regular basis).
It seems weird to come off as a pious man, and then to just be like radio silent, says far more about the person, than anything they themselves can say.
But honestly, it doesn't surprise me in the least. Not only because humans by nature are sometimes weird about this stuff, but also just how some people will be a certain way when it benefits them to be a certain way (a friend of convenience).