I think you're missing the feature of equal-weight index that your parent comment is attracted to—which is a sense that the market generally is out of balance toward AI investment at the moment and that there's a correction coming, which the equal-weight index will have less exposure to.

Your concerns sound valid provided things continue on as they have (I'm not a financial advisor and this is not financial advice) but the commenters above you are specifically worried that it's not going to do that. In which case, the disadvantages you point out of the equal-weight index will be handily outweighed. If an AI bubble popping causes the market-weighted funds to suffer, it doesn't matter that we've avoided trading fees along the way.