Possible rollback after introduction of Cities Skylines launcher?

[TinyWiking]

After the latest update Paradox and Colossal put a new software on my computer without my consent. I now want to roll back the game to the previous version before the patch. So I can play the game I paid for without having to have the horrible bloatware/spyware. Is there a good way to do this?

No, there is no way to roll it back, and the honest answer is that I don't know why we don't have this option for Cities (since we have it on PDS games). Furthermore, if you think this is "bloatware/spyware" you are very mistaken as it's neither of that, it's just a launcher. For reference:
Spyware: https://en.wikipedia.org/wiki/Spyware
Bloatware: https://en.wikipedia.org/wiki/Software_bloat#Bloatware

same here. i just want to get rid of the software they installed on my computer without my permission. i wonder what eu gdpr says about this.

We don't need your permission to update the game, you already gave it to us when you agreed to the Terms of Use:

12. Updates to the Services.
For the purpose of improving its products and services, Paradox may require that you download and install updates to the Service and to the Games you have installed on your computer. You acknowledge and agree that Paradox may update the Service and the Games on your computer, with or without notification.
(https://legal.paradoxplaza.com/terms-of-use?locale=en)

And before someone goes "But it's not part of the game!", yes, yes it is. It was implemented with a game update and is (now) an intricate part of the game.

This thread is locked as the OPs question is answered and I've clarified some of the misconceptions that have crept up.