What's more, most smart devices will not last until 2038. Planned obsolescence is a standard feature of smart devices product development plans today, especially since fewer and fewer of them are doing anything without cloud integration. If this trend continues, I would bet a kidney that no smart product launched in 2025, regardless of target audience, will still be operating (and be incapable of receiving updates automatically) in 2035.
Protocols would change way before then. 2038 is 19 years in the future. What devices from 2000 are still running, that wasn't running long before 2000?