they have intensified flights to Kaliningrad and the shortest route has to skim estonian lithuanian and latvian airspace, I can't see why is that a provocation
I don't know why they fly more now, maybe because fuel is quite cheap these days so why not
Its because they are convinced that Nato can be destroyed by a single attack against the Baltics, a land bridge to Kaliningrad will be easy in their eyes, give the their view of Europeans as cowards who are incapable of fighting.
This is how Russians view themselves -
And much like the Germans after the First World War, they have convinced themselves that the Soviet Union didn't lose the Cold War and they want a re match.
The only thing that will stop them is a military defeat.