While it's true that a business won't shy away from leaning on its intellectual property to beat out competitors when necessary, it is also true that having you

While it's true that a business won't shy away from leaning on its intellectual property to beat out competitors when necessary, it is also true that having your own strong patent portfolio is one of the best defenses against patent lawsuits from competitors and (some types of) patent trolls. It's sort of a mutually-assured destruction thing, where they won't sue you over X because they know you could sue them over Y. There is also the possibility that if you don't file the patent, someone else will, and it's better for you to be in control of that property than to leave it for someone who is potentially much worse to obtain. This is pretty much the dilemma involved in any willful abdication or refusal to seize property/power. It's particularly relevant to competent engineers who opt out of office politics because they dislike the BS, which means the task is left to the incompetent. This results in suffering for everyone. If something is under your control, even if you're not actively doing much with it, you're preventing an adversary from taking it instead.