This is like saying it's hard to make chocolate, tea, or many other ultra-popular foods/drinks palatable.
Step 1 of 1: add sweetener. Not hard at all.
Many people (including me) would argue that coffee is delicious without sweetener, though. Perhaps you don't understand how people like it, but that's far from a universal opinion.
My theory/speculation is that if you consume something that tastes badly but makes you feel good, the human body will over time translate the expectation into "this tastes good".
Maybe that's part of how addiction works. Maybe that explains "acquired tastes". And maybe my uneducated guess is completely wrong :)
probably things like mild peer pressure, fitting in with the grown ups, etc, much like smoking, and maybe even drinking.
Yes, social factors increase usage of all these things and people will force themselves to do it, but that's not universal.
I also love the flavor of smoking tobacco products (including cigarettes), although I only smoke a few times a year for social, health, and convenience reasons.
obviously, tastes vary strongly, so both groups must exist.
in my case i escape the peer pressure by discovering that strong coffee actually made me sick, and i used that as an excuse to reject coffee even in situations where it was considered impolite to reject an offer when i was visiting people.
Now I've "matured" and realized coffee is a drug. Or, if you will, a medicine. You don't take medicine because it tastes good, but because the effects are, on balance, good for you.
Though I was thinking of the caffeination of the workforce. And coffee has more of that than tea.
But coffee is (1) addictive, and (2) induces wakefulness and action.
I've seen loose theories that coffee was the real reason for the Industrial Revolution. It's not hard to imagine the extra energy it produces to also go into political efforts.