What could break an app download from the Play Store? I cannot pinpoint exactly when it started, but I'm starting to get a lot of users complaining that they cannot download my app from the Play Store, the download always stops at 89%.
Users can download other apps, even bigger ones.

I tried to reproduce but to no avail. Could some antivirus prevent the complete download?

App bundle size is approximately 50 mb, the issue appears on a variety of devices and different Android Versions. Available storage space does not seem relevant.

I am aware that it is common for Android users to not be able to download apps for various reasons (lack of space, wrong configuration on user device), but here the issue seems to be that they cannot complete the download of this app in particular, it always fails at 89%, and it started recently (but I cannot be sure that it is linked to a specific release). This app has more than a million downloads and all my other apps are unaffected.

Update: an user told me it worked when he tried to download the app again
If you use a bundle format then your app is decomposed into several chunks for different languages and screen resolutions. Maybe one of these chunks cannot be downloaded or it is broken.