I can see where you're coming from because of outdated libraries and flatpak sandboxing not really being a thing (it's an illusion, really) but you can't deny that this is the direction we're moving in, and we need to get flatpak sandboxing and permissions right, to ensure a proper base level of security.
For those unaware:
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Many flatpaks use older, outdated, or end-of-life libraries
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Flatpak permissions are messed up because most applications ask to bypass the sandbox at install-time