The monopoly ruling that you are referring to IS focused exclusively on search engines.
Excellent, let's review an incomprehensive list of competing search engines:
- Brave
- Bing
- DuckDuckGo (previously mentioned and you ignored)
- Yandex
- Kagi
- Yahoo
- Baidu
- Ecosia
- Qwant
- AOL
In short, Google has WAY more competition in the search engine industry than Steam has in the PC game purchase industry. So maybe learn WTF you're talking about before being a dick.