I haven't given it a lot of thought, but I tend to agree with you. The sister comment to your comment (about AAPL and it's tracking/privacy changes and the effects on other companies) is a good example why. Some externalities may be realized as effects on other companies that may be part of a portfolio, but some may not be. For example, what about how users value their privacy?

It's a very interesting legal approach, but that doesn't make it right. Externalities are very tricky.