Brave allows you to do whatever you want. You can see publisher ads without Brave ads. You can see Brave ads without publishers ads. You can see both. Or you can disable both.
Since individual users can achieve any configuration of ads they like, to me it seems that some people are only unhappy with this because they want to push their moral stances on everyone else. Like, for example, stating that the ability to block publisher ads while enabling Brave ads is immoral and shouldn't be allowed.
Brave basically aligns advertising incentives to match with viewer incentives. A Google served ad is not the same thing as a Brave served ad from the perspective of a viewer, because Brave ads are optional and some of their value accrues to the viewer.
Is the alignment perfect? No. But I do view it as a substantially better starting point than the currently centralizing, adversarial model that currently exists.
On one side, Brave come with an adblocker that will remove any ads from the website you're visiting. On the other, they provide their own ads through the reward program.
So it can be seen as "replacing website ads by its own".
I approve that line of reasoning, but I think that what the author meant.