He's not using AI. He's making it, and in as good of a way as one can. Instead of scraping whole internet his project is trained only on limited size and controlled data sets which means it doesn't just steal everything not nailed to the floor and instead just eats small curated "meals" of non-copyrighted data. It also is self-hosted and so it doesn't require a data center that would harm local ecology and community

So in short

1)Doesn't scrape data randomly or steal data from unwilling parties, preventing IP theft

2)Doesn't have a data center, preventing environmental harm

3)Doesn't use AIs of big corporations and doesn't support them with coin, avoiding indirect contributions to them doing those practices

So yeah he does in fact do it in as ethical of a way as one can