But flatpak also brings a lot of bloat. That’s the point of these 2 formats. You are trading bloat for portability.
The question here is not which one but why not both[*]? Also the target audience for this distro doesn’t know how to add repos, that’s the point of it.
[*] the answer is that Snap Store has had malware in it multiple times but that could imo be solved by a disclaimer
mainly hobbyists or some very specific feature. For example antiX for old hardware or Spiral Linux for the better installer, gaming specific distros for gaming etc. Also there are protest distros which advertise not having something - usually SystemD.