I'm astonished that there is still no Linux Kobo app available at
https://www.kobo.com/gb/en/p/apps.
The app., if the Kobo firmware is anything to go by, probably includes OSS/GPL software, so should probably better be put in a GitHub repo, so that others can fork/contribute, rather than just some seemingly shady old binary-only download, which is probably far out of date with Kobo APIs/auth, possibly dependencies too, etc., if it even still exists.
Linux is grown a lot since 2015, including gaming support. I migrated from Windows 10 Professional because the damned boot stopped working again, and couldn't be restored; I had enough, so switched to Linux Mint MATE, which is generally far more usable now, especially for development, with many tools migrated to, and even only available for Linux. Some development/admin tools seem to work better on Linux, too.
Recent WINE (direct repo, not Ubuntu/Mint repo) versions allow more finicky Windows applications, like Directory Opus, to work better on Linux, but not so much for USB yet, so we need a proper Linux app.
Kobo is still relevant, because some books can be cheaper than Kindle or not black-listed by Amazon for specious political reasons.