I'm going to assume this question was in good faith, and ignore that you are seemingly spamming it as a 'gotcha' all over this discussion.

If I'm already invested, and they change the rules on me in a way I don't like, I have to sell, and that's a taxable event.

So if I have invested in a Nasdaq index, and I don't want a massive exposure to SpaceX prematurely, I am forced to close my position and immediately pay taxes on the profits. I pay the taxes, and now my investing capital is reduced because Elon wanted to force index funds to buy SpaceX stock, which indirectly forces all current owners to buy SpaceX.

It's not future buyers so much as people that are already exposed, and were probably not counting on getting rug pulled by the Nasdaq.

So no, you are correct that no one new to investing is forced to own SpaceX stock, but millions of existing fund holders are now exposed to a stock in a way that simply wasn't possible when they put their money in, and will be penalized if they don't want that.