I’m afraid I very strongly disagree with most of what you say. Your comment on AdWords is valid, and this is because Data Studio is an addon to the Google Marketing Platform. In my opinion, tt should be viewed in this way and not as a BI tool.
It has no data governance, no proper permissions management. Outside of Google marketing products its connections are awful. You’ve said that connecting to Google products in Tableau is difficult, but I connect to Bigquery with 2 mouse clicks. On the other hand I’ve had to jump through more hoops using Data Studio.
Tableau has been around for 15 years now (which is significantly more than 5). The frequency of updates and adding features to Tableau is very high.
Going back to the data governance piece. You’ve said that the security on Data Studio is good. For me personally, their security is my biggest issue with the product and why I’m working as hard as I can to eradicate it from my business. Admin rights for managing the data sources mean that you can’t track data lineage properly unless you’ve had a data source explicitly shared with you, tracking who has access to what and what even exists is incredibly challenging. There’s no such thing as an admin user that can manage this.
It’s encouraging that you’re taking an interest in BI, but I implore you to take some more time with Tableau and understand the value it delivers. Data Studio is ok to whip something up quickly, but you can’t build a platform on it, and you can get yourself into a real mess with it very quickly. I personally think it’s a dangerous and irresponsible tool for Google to have released. But that’s just my 2 cents.