There's nothing funny about it.
It's a great concept invented by a civilization better than ours in labor concerns, that we have failed to maintain because we allowed greed to overturn everything after the 70s.
Retirement is as great an a civilized invention as universal healthcare, schools, legal system, etc.
It's just that our societies are not worthy of it. Compared to a society that can, we're like primitives that throw disabled kids or elderly to the wolves.
>but we act like everyone is supposed to just sit on a golf course once they turn a magic age and live happily ever after without needing to earn a dime for the rest of their lives
Doesn't have to involve a golf course, but yeah, what's so strange about the situation you describe? For one, people pay all kinds of taxes throughout their lives for that. Second, it's not a "magic age" but a median age (which can change over time) when people no longer cannot realistically work (strength, health problems, etc).
I'd like to see you at 65+ with no retirement money and no job prospects, how that would change your tune...