The way you share quotes sounds like you personally have a problem with the browser :D

Kiwi was started as a fun+independent project, then more and more people asked access to some source to be able to develop their own hacks (new tab page, extensions, bottom toolbar, import/export bookmarks, AMP, etc) and they are shared when the devs ask politely.

At the end of the day, if you use Samsung, Kiwi, Fennec or Yandex, what matters is to understand why the developers are doing their project, what do they get from it (not necessarily money), and what are the influences around. The source-code is one indicator, and, unless you actually have reproducible builds (and only Fennec has them from all the mentioned browsers) you have to use your intuition.