Earlier quoted context omitted.
Because the tool can generate output faster than human employees alone can (and they control the "legitimate" gate by which other people can use those characters in the tool). The consequence being that for everyone complaining that AI is disrupting artists right now: these will, in hindsight, be the halcyon years. Even if we assume the copyright arguments hold water in court and AIs trained on other people's copyrig…
Art isn't a volume business though.
To the extent that art intersects capitalism, that matters (even if the second artist is charging thousands per work; when your price is too high, people can't buy, so the artist charging dozens or hundreds per work but making 5,000 a year can sell to all the people who can't afford five-works-a-year).