then why not have an annual "please help us keep the government running tax" and at least be honest? Why invent taxes on things that don't make sense?

A tax is usually applied to help facilitate maintenance for something you are using. Or to disincentivize "bad" behavior. For example i pay taxes in the US that directly help pay for public schools, the fire department, roads, etc.

How does the french government bear any cost if i download data from a data center? What bad behavior is disincentivezed with this tax?

Gotta make sure those pensioners are raking in more money per year than the people actually in their prime working years take home...

So why dont we tax air? Everyone is breathing all the time, if the point of a Tax is to raise revenue we should be taxing every breath

Oh yeah you also have to not kill the population economically. What about the citizens who are doing large scale research on datasets? Those are the ones who are going to make billion dollar companies and they wont happen if they are watching the meter all the time because the government has decided to tax thought, so better not think too much!

Which side of the Laffer Curve are they on?