Most Rosewill PSUs were as bad because many of them were the same PSUs under different names. It's only a few of Rosewill's PSU lines that are good. You are correct in that Cooler Master, unlike Rosewill, did try to lie about how good their PSUs were whereas Rosewill just didn't say much about theirs.
A PSU doesn't need to be high-quality to be Gold certified. Technically, it just has to meet the requirements for Gold certification such as PWM and the efficiency requirements, granted in practice, there are many Gold-certified PSUs that fail to actually meet the efficiency requirements. I agree that they
should be high-quality, but not that they need to be to be certified so long as they meet the minimum requirements for that certification.
I don't know of many companies who don't lie or at least tell misleading truths. That doesn't make Cooler Master not guilty, but many companies such as Intel, Nvidia, and more have done such in the past and continue to do so in at least some ways, yet we still recommend them where applicable. I understand arguing against Cooler Master for these reasons, but keep things in context if you're going to do that