OP is still a very new Linux user (if at all) that hammers on stability in every one of their posts.

Ah, I missed that nuance. In such a case, I always recommend one of the big three, Ubuntu, Mint, and Fedora. When they've been using that for long enough to know what they don't like about it, it's a good time to start exploring the wider ecosystem.

Even with Arch and Debian

Yeah, they've been around long enough that I'd be surprised if they vanished. I would add openSUSE and Slackware (even though it's a one man project) to that list. Of course Patrick Volkerding could get fed up with maintaining Slackware at any time.

And (often) comes with tons of support/discussion across the internet that will prove to be useful for the new user.

That can be a double-edged sword, especially if the distro has been around a long time. What the user finds can be out of date and now just plain wrong. Ubuntu definitely suffers with this.

Please feel free to provide other metrics that OP or others might appeal to.

Besides longevity and adoption, I would argue that whether it has new enough drivers and firmware to support your hardware is the most important metric out there. For example, if your hardware is newer, you should likely choose Fedora from the big three.