Because they have no spine and no leverage/muscle on the international stage to throw their weight around and make sure they get what's best for themselves at the expense of everyone else the same way US, China, etc do.

They play the international nice guy that just ends up being the doormat everyone takes advantage of, being at the mercy of Russian and Azeri gas, at the mercy of US tech, energy and defence, and at the mercy of Chinese manufacturing after dismantling their own manufacturing, at the mercy of Turkey for migration enforcement, etc so they can't do anything radical that upsets their "partners", or that makes their virtue signaling policies look bad, or risk massive repercussions they aren't prepared for, so they just turtle, bury their head in the sand and pretend everything is going fine while falling further into obscurity.

EU flaunts its "moral values" as its strength, but their geopolitical adversaries have no such values and are dominating over them in the process exploiting their morals against them as their weakness. There's nothing virtuous in being/acting weak and letting others dominate you.