But in France there is separation of powers. No politician, including the president, have the power to make arrest people.

Also, in France, when you are arrested, you can be kept in "garde à vue" for as much as 48 hours (sometimes more but it’s rare exceptions) and during this period, there is no communication whatsoever.

It’s then up to the prosecutors to either decide to give up or to go to trial. If there is a trial, it will be a public trial. Like, any French citizen can just get in and out the tribunal during the trial whenever he wants.

So even if it was a political arrest (which it isn’t because it would be useless), Pavel Durov couldn’t be retained more than some days.

So yes, a lot of noise is being spewed to try to turn everyone against this before any details are actually public.