Can I launch Blender there and will the experience be comfortable?
You could probably get away without the mouse if you're ok with touchpad usage. But YMMV.
Stop imagining. I'm quite literally mooching around in bed posting this from Firefox on a Steam Deck in desktop mode docked to my bedroom TV. This[1] isn't your father's Oldsmobile.
[1] https://store.steampowered.com/steamdeck/#SaleSection_24468