In the Spain of my youth, the regulation was way past avoiding a monopoly in commodities, and full on to protecting any incumbents on anything, like mom and pop retail.

One example was (and maybe still is), to ban discounts on textbooks, as the big margins were a big reason small bookstores stayed afloat.

Another was is to limit hours of operations in stores, including making stores be closed on sunday being mandatory, as many family retailers just couldn't man the store without hiring someone, and labor laws made hiring someone for little time expensive.

There was also a semi-recent outcry when the government stopped regulating rent hikes. for commercial property. There were plenty of stores in highly desirable locations that were on the same lease for a century! Their monthly rent could be two orders of magnitude away from the space next door.

Such level of protectionism of old business models just means that instead of going through pain and optimization for decades, they all get wiped off the map in one fell swoop the minute competition that can skirt the protectionist regulations comes in: Imagine what happens to tiny stores when, instead of first having to compete with US levels of efficiency in big box stores, they get to compete with Amazon. What happens to record stores that can get away with selling music for 25+ euros an album when spotify shows up?

So, while there is reason in fearing monopolies, the levels of regulation I describe just have little to do with what the US calls anti monopoly regulation.