...as you don't actually injest the leaves as you do with the coffee...
BLEEECH!
Personally I don't like grounds in my coffee and I don't ingest them. And they're beans not leaves
But you're correct about the caffeine levels, depending on the way the beverage is brewed of course. Being curious and not looking at numbers for a while, I looked

and was a little surprised it wasn't quite how I recalled it. The so called "energy drinks" surprised me. Maybe they've changed them as I recall them being higher. Maybe that's why they don't do it for me anymore?
Coffee will average about 60mg/oz for espresso and 20mg/oz for brewed. De-caf of either is down to 0mg/oz though a de-caf espresso can be as high as 15mg/oz which is more than some full brews.
Tea averages about 4mg/oz with de-caf varieties being 0mg/oz.
Soft drinks, what I call "hard" (caffeinated) soft drinks (Coke, Pepsi, Dr Pepper, etc.), are pretty consistent at 3mg/oz, less caffeine than even tea (except de-caf tea of course). Even Mountain Dew is only about 4mg/oz.
Energy drinks (generally) average about 10mg/oz which is still less than even brewed coffee. Makes one wonder what all the hullabaloo is/was about kids "abusing" them.
However the "5 Hour Energy" shot-type drinks are about 100mg/oz.
And of course if you are caffeine intolerant there are many over the counter medications to avoid as they can have quite a hit of caffeine in each little pill.