As I said in the last thread on the subject of secret conspiracies, it was clear from day one that the cause here was neglect--the PC version of this game is at most the fifth or sixth most important SKU. It's not about deliberately worsening the product, it's about neglecting to invest resources to improve the product. They developed with a certain baseline level of effects, they toned them down to improve performance on the console SKUs, and then they chose not to finish development and testing and refining on what they already done. And as is normally the case, the final build contains cut or unused content. Many games even have playable, very near completion cut content. It happens.
The deception here is that they somehow got from "This is PC only, who cares" to "the dev team is completely dedicated to getting the most out of the platform". I am sure the dev team did their best given the resources and time constraints and the organizational nightmare of working on a game made by 8749 people across 271 teams in 181 countries. But it's pretty clear that knocking the PC version out of the park was not their priority. It's okay, but it's also something people should be aware of before purchasing.
I do think patching out something that was only accessible through a mod is pretty poor form. 99% of the players wouldn't have touched it and the 1% who would have would have done so with the understanding that if stuff broke, it was the mod, not the game.