I guess, given its popularity, Google won't kick Telegram off the store for obfuscating the URL and using an unauthorised (?) API endpoint but I imagine this will get them in some sort of trouble.
I'm not sure about this.
I bet Google is happy to collect the text data of up to 500 million users with zero restrictions from Telegram's end on how the data is used. I'm not a lawyer, but my hunch is that Google's data privacy policy applies to the official, premium service: https://cloud.google.com/terms/data-processing-terms
Google might make the determination that they'll get more value from allowing Telegram to abuse the unofficial API. However, they might face some angry customers who are paying a premium to use the official API now that this loophole has been published.
Although at the same time half my friends use it at our (critical) communication platform. So it's not in our best interests.
In general I am pro Telegram, as I think any democracy needs to have censorship-free communication for whistleblowers etc. and to prevent attacks against democracy itself. Even if this means we have to live with stupid/illegal opinions being expressed too.