The issue isn't that accepting money is ethically wrong, the distinction comes when you're charging for it. Donations and the like for mods have always existed, the difference is that they weren't paywalled. Just because you created content doesn't mean you should be able to charge for it, I can create a fanfic about harry potter rapping his way to the top on the streets of NYC, doesn't mean I can charge for it. Any mods that are big enough to even come close to being worth money, that is, reaching the $1 per hour of content, couldn't be sold because of how much they rely on other mods to function.
why not? is the work any less-valid?
like if you just throw a bunch of assets and code together you didn't make, that's one thing, but if you spend a significant portion of your free time to make unique content, why wouldn't that be valid enough to justify charging for it? i'm not sure i completely understand the idea that content isn't real content unless it's standalone. what makes the content less-acceptable in that respect? i just want to know where the logical line is actually drawn between generated content that is acceptable and unacceptable for payment. it seems natural that if someone creates a work, they should be able to charge for it, and if they charge too much, their work's success is hindered as a direct result. this is the same for youtube, for games, for arts and disciplines in general. it's why commissioning works and why youtube partnerships exist. people that dedicate themselves to delivering unique content for the entertainment and enjoyment of their audience should be able to profit if the situation is appropriate. not to mention the less-relevant incentive monetisation provides to talented individuals who don't mod simply because it isn't a profitable allocation of their resources; individuals who could provide fantastic third-party content to games if they knew they could make a worthwhile investment of their time.
in addition, the review system exists for mods (existed? did valve really remove it? if so this can be interpreted as "why reviews should be a thing for mods" as well) for the same reason it exists for games. games that aren't worth the money the ask for are reamed for it, and the same will happen for mods. if a developer charges more than their product is worth, they're ultimately only hurting his/her self. reviews allow the everyman to play a role in the market by putting the word out there that, "this is terrible," or, "this is amazing." that's also why the downvoting raids are fairly ridiculous, because they don't play a role in demonstrating an opinion on the work itself, but rather the fact that it isn't free, which unfairly distorts the review system in such a way that decent works are punished by the community for a reason irrelevant to the actual quality of the product itself. and that's equally why removing rating and reviewing would be ridiculous, because it takes away that system so that the good and the bad are indistinguishable aside from marketing slips which indicate poorness
