Firefox is better than most, no double there, but at the same time they do have some shady finances.

I'm not going to refute this because it seems to me that article are right in several points. Also, we have to be honest, Mozilla is kind of stupid sometimes.

But if you care about the default search engine or privacy settings, you really just need to do some hardening and tweaks to make it very private in general. Chromium doesn't have any of these settings, it even doesn't have RFP btw.

and they also do stuff like adding unique IDs to each installation.

Looks like you can download Firefox through the Mozilla's official HTTP/FTP repository that doesn't trigger this ID token generation. Also this article motivates people to download Firefox installer from Softonic's page:

Firefox users who prefer to download the browser without the unique identifier may do so in the following two ways:

1. Download the Firefox installer from Mozilla's HTTPS repository (formerly the FTP repository).
2. Download Firefox from third-party download sites that host the installer, e.g., from Softonic.

Softonic have a really nice and privacy respectful privacy policy (obviously that's not the case) in contrast with randomized pretty anonymous unique ID triggered by Firefox installer download. Mozilla's generated ID feels more like a download counter than a tracker indeed.

I'm not trying to justify the Mozilla's problems. They makes silly things sometimes, but being realistic, they do a better job taking care of their users privacy more than Google or even Brave.