''The browser is available in Beta, and Canary channel''
There is no beta yet....

Effectively it is a beta even if it isn't called that.

No; beta is a separate channel that we're still waiting for. Dev is another alpha, just updated a bit slower than Canary.

Alpha normally means unstable and flakey, which Edgium is definitely not.

It doesn't matter. alpha/beta/etc. is a statement from the app author of what they declare that version to be. If one alpha build turns out to be incredibly stable it doesn't make it a beta or a stable version.

Also, since MS uses Canary/Dev/Beta, Beta has a concrete meaning and using that name to describe Dev would be misleading at best.

There is a common use meaning and MS's specific meaning. In this case they have clearly diverged. It is not one build that is incredibly stable. Even the daily Canary builds have been issue free since the first couple of weeks.
There was a trend a few years ago for companies to leave their products with a perpetual "beta" tag which is what we are seeing here, and it is probably more marketing than product driven.

This is really not what's happening. First of all, there were a few critical issues in the past months and there will be more from time to time. Canary is definitely not stable. Secondly, there's no MS-specific meaning here; Edge channels just follow the Chrome channels naming; Edge dev ships more or less the same code as Chrome dev does and there's no channel that ships what Chrome stable does at the moment. When they're ready to go stable, they'll release stable.

In the rolling-release model that most browsers follow these days the alpha -> beta -> stable cycle is short so the typical "alpha slowly gets more stable & when it gets stable enough we mark it as beta" model doesn't and cannot apply here.

So we come back to we have a stable end product, even if MS are basing it on the Dev and Canary channels of the rendering engine. It is essentially a mature product that is getting some minor changes every now and then, and may receive some extra features in the future. It may not be what MS ultimately envision but it is from a consumer point of view as stable and usable as any other browser.
The only significant issue is a user agent string that causes YouTube to serve adverts rather than content.

I dislike Chrome almost as much as I dislike Edge...

Firefox FTW. :)

Add Timeline support to Chromium Edge and everything will be fine. I know, there is plugin for it, but I want it native in it, without any installation

That would be bad.

Honestly I've been saying for years Microsoft should have either bought or switch to another browser. IE and then edge were jokes compared to the features and power that we expect from Firefox and chrome

Tying IE to the OS is what killed it. A browser can't evolve if it's development cycle is tied to a slow moving behemoth like Windows.

Microsoft also won the browser war so stoped bothering to develop it. It was never popular anyway though.

Microsoft did not "win the browser war". They won some early battles. The war continued, and Microsoft stopped fighting. Worse, they surrendered and then joined the other side.

The true "winner" is Google.

I have a differtent view of this situation. Google was the only one messing with chromium code as they wanted. Now Microsoft will also direct chromium future. Also, people usually use Edge to download Chrome, but if Edge is Chrome, this will likely not happen. Google Chrome user base can be reduced. And I didn't even mention Mac OS and Windows 7 version that are now fields where Edge can now compete.

Those are good points, but there is still a fatal flaw here. Microsoft should NOT have kept the "Edge" name. It is a new product, it desperately needs a new name. Its not as if "Edge" has a long, proud history as a product.

The same reason that they dumped the Internet Explorer name and called the new browser Edge. However, they made another fatal mistake there, by keeping the same icon. Everyone assumed it was a new version of the same, crappy browser. Turned out it was a different, crappy browser.

MS has a long history of bad browsers. Keeping the Edge name only keeps that history alive.

Are you kidding? Features didn't failed. The browser as a whole failed. Set aside tabs is one of the top features that is missing from Edgium.

Yeah many times, when I was doing any project work which required several tabs opened and several hours to days of work.
Another instance is when planning for a travel. From choosing a spot, then mapping, then booking tickets, booking hotels all at suitable rates. It requires several sessions. Also it can be helpful during large shopping spree with comparison and review.

Later when Firefox Quantum came, I shifted to Firefox and found Session Sync extension. Which is Set aside tab feature on steroids and 100 times better. I can't find any extension in chrome which is as handy or as practical as Session Sync.

And if Edgium just remains a copy of Chrome, basically most of the people won't move from their 'TRUSTED' Chrome.

Actually yes, i do use set aside feature on a daily basis, either to save recent website nor pdf.