I’d say the point is more subtle than that: it is not mere efficiency that comes with such scale. Rather, such scale is necessary to enable certain technological investments and long-term risks and behavior. For example, if you were a non-monopoly company in a competitive environment you would not be able to steer Chrome and shape it the way it is. You’d be burdened by day to day business needs to keep the margin from eroding below zero at any given corner.

Under this theory it follows that if you actively kill any business with a monopoly market share like the EU, you’ll guarantee failure for the society in achieving certain technological breakthroughs. The only way to avoid it would be government sanctioned corporations (CCP style) or US style pre-Lina Khan relatively free market approach to scale.