The theory is that by hiring cultural consultants they can avoid this.
I'm somewhat sceptical because there's no guarantee that two different people from the same minority group will actively agree about content. I've read accounts of journalists getting into trouble for articles and people blasting them for not using sensitivity readers when they insist that they did use sensitivity readers.
Which is not to say they should not be used, but they are not a cure-all and independent creators may not have the funds to pay them.
I think it's more the larger companies that ought to worry about hiring cultural consultants and/or sensitivity readers. If independent creators are worried about their use of real world cultures or other issues, they are probably already more sensitive to those as they are designing their product, and if they work with editors or play testers, are more likely to find people who are likewise aware of potential issues. In fact, larger companies like wotc could learn here by hiring designers and editors who are already sensitive to potential issues. (For example, Tomb of Annihilation received
some criticism when it came out (though it's still a broadly popular book, so I don't think the criticism really hurt their bottom line). The linked article contains the line, "When I asked, Perkins said that no black writers or consultants worked on Tomb of Annihilation." Wotc certainly has the resources to fix that!).
I'd also make a distinction, subtle as it might be, between
preventing offense and
preventing harm. Preventing offense strikes me as something that, again, larger companies are concerned about. Wotc or Paizo wouldn't want bad press, or twitter controversies, because those are bad for their bottom line and bad for their brand. Independent creators, on the other hand, have smaller audiences. In the case of ttrpgs, that audience might very well be under 100 people. In that case, creators maybe have a better picture as to who is playing their game, and their games are not likely to elicit much response, if any, online (either positive or negative). But also those creators might be more concerned with
preventing harm--making sure the people who read and play their games are comfortable and don't feel invalidated by, say, real-world analogues or by inappropriate representations of disability.
Moreover, a mindset of preventing harm would recognize that it's an ongoing process, and if you mess up and people notice that's not a bad thing ("bad press" etc) but a chance to learn and do better. I think when you approach these issues with that mindset you earn a lot more credit from audiences. And then it also becomes more about listening to your readers rather than paranoia about people "getting offended."