That is not true at all lol, unless you're already well established, and only a very small group of people are being pressured to use a service they don't have an account on(me included). If you're just starting, or just about to expand your customer base online(in the way that make sense to the type of your business), going to where the customer are is the only choice. You can totally have multiple platform but that also not making people shift platform, people just won't bother with you if you're not on the platform they frequently use.
Also, as a customer, i'm definitely won't bother to create an account on Meta just so i can interact with the businesses(whatsapp is the sole exception), but if i were to start a business i'll have to went out of my way to find customer, which is whenever they are.