Except nobody was "investing" (speculating) on GNU Herd. It should give a lot of people pause that Bitcoin can just suddenly split like this. What's to stop it from being split again and again?
What should give us pause about that?
Even if I had a million dollars in funding, that would buy me mining power for oh so long. All the meanwhile, If I change the rules too much no one would even attempt to join my fork.
Even If I had another million dollars to pay developers to build services on my new fork, there'd be no users and no economic activity. The fork would die.
There SHOULD be a lot of hard forks. Why? Because they're voluntary and most will fail without doing harm (they require consensus to matter). The good ones will survive on merit and act as protocol upgrades.