SOLUSfiddler I agree with the main points of your comment. For people trying to get away from Windows it just doesn't make sense to run towards these new products which simply tangle them back up in the Microsoft walled gardens and data collection. You are I run Linux for the same reason.. privacy, security, and control over our devices.
However, playing the devil's advocate, I can think of a number of reasons why Linux users would want to install the Edge Browser.
Some people just like browsers. There was a time when I had every browser under the sun. Remember Torch? What a cool concept! Yandex is still one of the best browsing experiences I have had to date. What about Waterfox? Pale Moon? Sea Monkey? Epiphany? Maxthon? Epic? That doesn't even include Opera, Vivaldi, Konquerer, etc etc etc.
I wouldn't touch these browsers now if you paid me but some people just like tinkering.. which is what Linux is known for.
Also I believe that many, many of the "IT Professionals" everyone thinks of when they think of Linux do actually work in the Tech industry and many have Microsoft and Windows certifications which require them to at least run Windows 10 which has Edge pre-installed. Some might need/want Edge for professional use cases.
There have even been several posts across the internet where I have seen people say that they wanted Edge as a way to keep all of the Microsoft/Windows based services under one piece of software so they would be able to stop mixing MSN and Hotmail and Outlook emails, Office, and Azure with their day-to-day browser.
One final reason that springs to mind as a reason to install the Edge Browser is those who are actively encouraging the open-sourcing of Windows and Microsoft products by making them available on Linux platforms. Many people (and I may be wrong but I would consider many Ubuntu users specifically) may be interested in running Edge because they genuinely want to test, develop, and give feedback to try and encourage Microsoft to tilt further towards open-source models.
When someone asks people like you and I, @SOLUSfiddler, why we run Linux the answer is 'to get away from Microsoft, and Google, and Big Tech, and Government Surveillance.'
But Linux is not an OS platform, it is a community of people.
Why do they run Linux?
Because they can.
Sadly many people may not yet truly understand the profound problems that arise from existing within Big Tech Walled Gardens. This is only my opinion but I feel it is moments such as these that create opportunities to begin a dialogue with those people on why running a browser like Edge is -not- in their best interests but also effectively communicating how using a proprietary piece of software like Edge can actually be a way to end the use of that same software.
Richard Stallman, Founder of Gnu Project, explained this much better than me in his article "Is It Ever a Good Thing to Use a Non-Free Program?"