What will stop Google to buy the next big video platform, US and EU did not stop them buy YT or FB to buy Whats App, if a competitor would show up the only way

What will stop Google to buy the next big video platform, US and EU did not stop them buy YT or FB to buy Whats App, if a competitor would show up the only way it could survive would be to be bought by MS,FB or other large company, this could lead to bad products or bad customer/user relations since this big companies are not known for their good customer support or caring for the users experience.