I completely get your fear as I also don't really want non-chat features from Telegram, but I can pretty confidently say I don't think any of the new features have at all changed how I use the app. my chats work exactly like I expect them to with my friends and that's perfect. I don't see any of the more social media stuff unless I want to.

I think it's a pretty good sign that all these social media features continue to be added and I still don't see any impact on how I use Telegram.