Depends. Unless you’re on Ubuntu or Elementary, Flatpak and Snap are optional. When I’m on Arch, btw, I don’t bother with any of those and just use the AUR with a helper like yay.
But I find the convenience of Flathub too good to pass up on other distros. I have been using Linux long enough to remember when the only options if your distro didn’t ship something were to compile from source or to use a sketchy installer script, because Flatpak didn’t exist. And as others mentioned, if you’re using a full desktop environment, it likely can update everything at once via the GUI.
That song is spot on. They’ve successfully turned the people against each other to the point where anyone who criticizes the side they picked gets written off as a nazi.