I used to be indifferent to the whole flatpak vs snap situation, since IMO either one is better than the traditional method of using the system package manager for everything. But now that I've had Firefox snap forced upon me by my distro, I've strongly switched over to the Flatpak camp. Snaps do literally everything worse than Flatpaks, offer a worse user experience, and they use a closed-source server for the backend.
I've been a loyal Ubuntu user for over a decade, but this Snap thing is making me seriously consider jumping ship to another distro.