They were competitors because they were competing for advertising dollars - that's how meta makes it's money. imagine this scenario: Meta comes to your company with a proposal to buy you out - they want your technology because they see the potential it has. Now, being the CEO being offered a butt-load of dough by this huge company you start seeing the writing on the wall - Meta wants to move into your AO and they have the resources to do it on their own and put you out of business or at least take a huge chunk of your market share...or you can take the money and run off to paradise. Walmart moving into a small town...