According to a report from sources speaking to SamMobile, Samsung is planning to end support for Bixby Voice on versions of Android that are older than Pie. This change will come into effect on January 1, 2020, at which point the voice assistant will simply stop working. There's a huge caveat here and a very easy fix. This only applies to Galaxy S9, S9+, S8, S8+, S8 Active, Note8, and A9 (2018) units that are still for some reason running Android 7.x Nougat or Android 8.x Oreo. So, only if you have any of these devices and you're still rocking Nougat or Oreo will Bixby's voice assistant...
Source: https://www.gsmarena.com/bixby_voice_will_stop_working_on_android_versions_older_than_pie_on_january_1-news-40284.php