Look for more of this in years to come. The costs of running large states are just too high.
It’s particularly irritating to Europeans who pay horrendous taxes and have tax havens on their backdoor like Monaco and Andorra.
Any evidence? There is plenty of evidence to the contrary -- at a municipal scale, for instance. Toronto saved itself by coalescing its multiple municipalities, and Pittsburgh is in the pits (pun intended) because it refuses to do so.
You must have overlooked such thing as economies of scale.