You said it yourself, switching would be a complication, and manufacturers are happy to maximize that complication as much as possible. I consider it unethical to impose artificial hurdles to switching upon consumers, especially when they most likely aren't familiar with vendor lock-in.

iMessage is a good example for me. It replaces a federated, universally-compatible service with a centralized service that works only on Apple devices. The upgraded features are nice enough to be alluring, and now a significant portion of American smartphone users feel compelled to remain with Apple so that they don't experience any difficulties communicating. This is a sticking point for me in particular; I used to be a heavy user of multi-protocol messengers like Trillian, during the time when multiple providers offered mutually incompatible messaging services.