Are you sure you're not confusing "monopoly" with monopsony? The former is about a seller vs buyers, where a single source has huge power over pricing and thus is able to raise prices for buyers far beyond market justification. The latter is when a single buyer controls a high enough share of purchases that they can exert significant power of sellers. While they both impact markets, they're not the same thing and they have different effects. The impact of monopsonys and to what extent their bad is a lot more controversial, because the fundamental idea of grouping together in order to gain enough purchasing power to negotiate lower prices from sellers is used in a lot of areas. I think monopsony does have implications for things like wages and working conditions, with outright depressing of wages as well as potential for more wage discrimination.

Those are all different issues though with different potential regulatory tools to apply against them vs a monopolist simply outright raising prices for buyers. I'm definitely concerned that way, way too many people have started to just reach for the big BREAK 'EM UP hammer for any problem they see, despite the potential for nasty battles delaying effectiveness and enormous and unpredictable side effects. I'd really like to see much more focused efforts tried first, particularly since a big central target can actually be easier to regulate and check for certain things. There is plenty of low hanging fruit at Amazon like their commingling practices, but such things tend to be more technocratic.

I'm concerned that focused efforts like that are seen as "boring" and in turn not getting the attention they should. This is similar to how I feel about other areas like secure hardware stacks. Rather then "break up Apple/Google!!!" I'd much, much rather see things like "devices owners must have the option to load their own crypto roots with equal power as any manufacturer roots" or "devices must be warranted for 1 month/$20 retail price up to 60 months" or the like done. They're not as catchy politics but they'd be really directly useful without risking a lot of the value scale can bring.