Gee, I wouldn't know, because again, the entire website tells me exactly nothing about how it works or what it's features are.
this is the only thing I could find that remotely details what it does. Amounts to little more than "It's a calendar"
There is Gnome Calendar. I didn't try it until now. But it seems to be rather simple and straight forward. I think I'll try it out. Works with Gnome Online Accounts and other local or remote calendars.
> There was an attempt to create an open source store, but it failed pretty quickly.
It was a "proof of concept" and worked OK (It was very short python code). The dev was only exploring and didn't want to maintain it. I don't think that means it "failed". If you want to create a competitor to the snap store, you can. The protocol is open ( https://dashboard.snapcraft.io/docs/ ), snapd is one end of that protocol and is FOSS. https://ubuntu.com/blog/howto-host-your-own-snap-store
> I do not want my free and open source software being built in and distributed in a proprietary platform.
You chose your license. It should express your wishes. If it doesn't, that's your problem.
> Even after many requests over the course of multiple years, Canonical insists in listing my application as developed by Canonical. It is also lagging 2 years behind the latest release.
It appears that the field you are referring to is "publisher" ... which the person/entity that uploaded the package. But they should make that more clear.
In terms of version: It is 3.30. I should note that the current GNOME Wiki ( https://wiki.gnome.org/Apps/Calendar/Download ) says that the current stable version is 3.28. The link to the unstable version is broken. If you can't even maintain your own wiki entry ... and still complain about other people having old versions, it seems a bit hypocritical. How hard can it be to update your own wiki entry???
I've also noted that you've put some of your code on github. Github is proprietary. If you don't like your code on proprietary platforms ... I suggest not using github. Or stop using that as a focal point of your outrage.
I believe what you was referring to was 3.24 with week view which is in a Prototype Stage.
https://wiki.gnome.org/Apps/Calendar/Roadmap
I always wait for stable releases on everything. That's how I been staying stable for the past 13+ years. Maybe you shouldn't rush to something that is new. Unless you like to try it in a VM or something like that. That way your system and system package stay stable.