The only actual monopoly in the tech industry is Google search. There is also a very concerning duopoly with Google / Apple app stores controlling all software loaded on mobile OS that needs to be forced to allow alternate channels. Besides that, I can't think of anything in tech that is actually a concerning monopoly. Amazon has no such monopoly position in e-commerce. The market share really isn't that big.
Even with Google search being so dominant, there are alternatives like DuckDuckGo, Bing, Yahoo. Many people are also starting to use ChatGPT as an alternative to some of the things they used search engines for.
On Android you can sideload apps, install alternate app stores.
Implying these companies are monopolies is an overstatement.
