It was. There are specific requirements in Article 102 about abusing dominant market positions to "apply…dissimilar conditions to equivalent transactions with other trading parties, thereby placing them at a competitive disadvantage".
If I owned a website that had a search engine and comparison shopping and email, I would not expect that it's somehow wrong if my search engine shows results from my service's comparison shopping and email.
If you owned a massive market-dominating service, then your team of corporate lawyers should expect that.
"You have to design new technology and build custom services that show business information for your competitors on your advertising/websites/properties"?
That's not what happened though – the specific instruction is:
the Decision orders Google to comply with the simple principle of giving equal treatment to rival comparison shopping services and its own service
That's all, and it is not unreasonable to impose these terms of a market dominating force that has used that dominance to crowd out competition.
What precedent is there for imposing rules this this on other businesses?
SO MUCH. http://ec.europa.eu/competition/elojade/isef/index.cfm
Yes it was [0].
> If I owned a website that had a search engine and comparison shopping and email, I would not expect that it's somehow wrong if my search engine shows results from my service's comparison shopping and email
If your search engine had a dominant position in the EU market and if you used that dominance to put your shopping product above other competitors', then yes, it would not only be wrong, but also illegal.
[0] https://en.wikipedia.org/wiki/European_Union_competition_law
What precedent is there for imposing rules this this on other businesses? "You have to design new technology and build custom services that show business information for your competitors on your advertising/websites/properties"?