I haven’t checked it, but at present (and in the near future) it should continue working. Google is enforcing this based on the targetSdk, so even if your device is API 29+ but the app uses API 28 it continues to function, and should do so for at least a few years.
There are two sides to this issue, both of which are relevant to ways in which Google is removing the method on which Termux relies in Android API 29.
-
Enforcement: Google Play stops accepting app updates which do not target API 29. Currently apps must target API 28 to be accepted on Google Play, and API 28 is what Termux targets. While this will become a problem, it can easily be bypassed by simply installing the Termux apk from elsewhere. This is expected to happen toward the end of 2020.
-
Technical: This will be the case if a future Android release enforces this security rule for all apps, no matter which API level they target, breaking backwards compatibility (including for Termux). This would affect all apps on a device, including those installed via sources outside of Google Play.
Google’s handling of security rules for target API 28 in conjunction with Google Play update policy indicates that such a technical change is indeed coming, but likely not for a few years.