If I were paying someone for access to such an API, I would do everything in my power to change providers. Tracking link expiration would be a terrible developer experience. Such a thing may be a sound design for a system, but it's not a good design.
Providers like Twilio and Stripe have been largely successful because they've aimed for making developer experience as non-sadistic as possible.
What's different about this proposal? It would seem to acknowledge and support that type of activity directly, rather than through ad-hoc and kludge type mechanisms that typically include paying somewhat shady 3rd-party services.