Hi @TONY-ROME,
While this is a relatively simple idea in theory, it gets complicated pretty quickly when getting into the the details...
The thing that I feel is the biggest inhibitor to this functionality (I know myself and others have discussed this in past threads on the topic) is that users can get notifications of an announcement via email, and those notifications are often the entire announcement. Canvas also has the ability to add announcements to the "home page" of a course. You may ask why these features matter in this conversation... It comes down to being able to track which users have open/seen something. The data about students who viewed an announcement directly in the UI should definitely be there. Tracking who viewed notification emails (which oftentimes are the announcement) is much harder and would probably be a frowned upon practice in general. Then with the home page announcements, those probably should be counted, but you could argue for a "no" to that depending how long the announcement was and whether you think students read that section of the home page pr not.
With these complications (and there could be more I'm not even thinking about currently), the number Canvas would provide is unlikely to actually reflect the reality of how many students really read the announcement. Maybe you would just like an wild estimate, but others would likely not be happy about that. It would also likely go down the slippery slope of further requests asking for data about which students read or did not read, and that becomes super problematic, as some teachers may even start to grade based on that.
Overall, my feeling as a Canvas admin for higher-ed is that while having accurate info on this would be very helpful, the technology doesn't really make that very possible at the moment. Until there would be a way to get more accurate data, I feel like it's better to not even go down this road. This is just my personal opinion though, and I'm sure others will disagree with me. I wanted to put this out here to show the situation may not be as easy as it first looks.
-Chris