In 2014 Google split their drive app into multiple separate Android apps for docs, sheets, etc. Obviously getting users to install and migrate to new apps would be a burden, so they designed a 1-click install modal that Drive could use instead of the typical redirect-to-Play-Store flow. Neat!
Around that time the company I worked for (large competitor of Drive) was about to split out some core functionality into a standalone app and wanted to use a similar flow for similar reasons - Nope! Google locked that API behind an app signature verification (not even a permission) so only Google signed apps could use it. No possibility to request the permission or appeal - just a hard-coded monopoly.
There ARE legitimate reasons that things like this can be risky and abuse needs to be mitigated, but there's a line that Google regularly crosses between abuse mitigation and anti-competitive behavior.