The mod seems to be a fellow Lemmy user (edit: oh they seem to be a mod of this community) and they're encouraging Reddit users to migrate to Lemmy, among other open-source software. Given the lack of care about dis/misinformation campaigns on Reddit on the part of the site admins, migrating seems like a good choice. If Reddit ever does take action, it'll only be when the bad PR outweighs the revenue that these misinformation people bring to Reddit. It's obvious Reddit doesn't care about its community, or really the massive role it plays in the current Web. If they're not going to take responsibility for the social damage they've caused so far by harboring and encouraging awful communities, then it's high time Reddit stopped existing.
If people on /r/linux do take the mod's advice, then there may be an influx of new users on the site. I think it may be a good idea to encourage them to shop around for different instances on https://join-lemmy.org or make their own, just like the Lemmy devs always encourage. Also, the [!firstname.lastname@example.org](https://lemmy.ml/c/linux) mods should be prepared in case we do get an influx of new users.