Bicycle Bottle Cages and how they have changed for cyclists

When I look back at the way cyclists used to cycle with the bottle on front of them, I always think it looks great.
Then when you look at where bottle cages are on bikes these days, I wonder what happened and did it change.

It seems like it was much easier to have them on front of you while cycling, but why did it move? Was it that it was too difficult to have them on the down tube when the bike's gear levers were there as well.
Surely though you could still keep the bottle at the stem even with integrated levers nowadays.

When you look at the bikes of triathletes, they very often still have their bottles on front of them as they cycle.
So when you look at these modern bike bottle cages they are always just designed to go on the bicycle's down tube.
This is how they all look now.

Is it still possible to get a bottle cage for the front of your bike besides the ones for a triathlon bike?
I only ever see them setup like above, but wouldn't mind trying to cycle with one sitting at the stem of bikes handlebars.