You should checkout flightsim.to. It’s a growing platform that already has overtaken all other portals in terms of downloads and visitors I think.
They have great functionality and every week the site is getting better and better. It’s partnered with MSFS Creation Reddit and has its own Discord that’s acting as a meeting point for users and devs alike.
Main thing I like about is that it resembles Steam Workshop the most. It gives you an option to get notified whenever a mod was updated, or you can check it every week or so and see which ones you need to download. I absolutely would not be able to manage 20GB mods without it, no way. A lot of people will mod even more heavily than I do.
Like you said nothing will replace GitHub for coding, day-to-day development and collaboration, and that’s where it should stay. However, I believe that major releases should be posted on that website. If people want more frequent ones you can always link them to your GitHub page on the add-ons profile. A320NX is on flightsim.to and that’s kinda what they’re doing - they redirect elsewhere but I still get notification if new version is released.
It’s fun to follow progress of many mods on that website. People put shirt changelogs that for example tell me “oh cool I should checkout new night lights at this new handmade airport”.
I think you’d get much more exposure by using it and I encourage other devs to do so as well. The more people benefit from your hard work the better.