Yes, sadly. And before somebody quickly interjects: he not just was not an a-hole, he was extremely kind, calm and always supportive. You almost never hear him say: "I am too busy right now, can we do this later?".

Seriously. Almost never.

Yep. Still got fired.

And he was not rising or anything. Was a small hardcore team, zero politics were involved, they were tight-knit, loved them. But there was only so much the CTO could do; it was a startup that was under the boot of a bigger org he was actually working in. He fought for good paychecks for everyone, and generous severance too. But had no say if the higher echelons said that somebody had to be let go.

There's no moral of the story except "don't sweat your job, they'll replace you the next day". Treat it as a transaction, not as a second family.