There have been no laws towards fostering competition within walled gardens in either the US or EU until now.
Apple had no app store competition until now. Do you contend the app store will not see material improvements in the future now that it finally has within bundle competition?
Why has Apple suddenly started investing so heavily in Safari over the past year, now that they will soon be forced to allow competing browsers?
If products have to compete on their own merits, rather than leaning on other aspects of a larger bundle, then software and products get better for all of society.
For example, if you were allowed to install any car OS you wanted, rather than forced to use the manufacturers, car OSes would improve significantly. Some people will buy a car for the hardware, despite terrible software. This is bad for the evolution of car software. If a manufacturer was forced to compete, they would have to invest more heavily in improving their software... or simply cede control of the OS to a better implemented third party one, and focus on the hardware. Both outcomes are better for consumers than allowing anti-competitiveness via bundling
Oh and BTW there are only two countries in the world, one of them is entirely comprised of GlobalSuperMegaCorp's monolith city-state company town, and the other is entirely comprised of company towns run by franchisees of OtherMassiveGlobalCorp.