Nah, I let my baby “sit” with all the pillow tucked around and securing her as well (but not too long), my LO is 2 and still alive and kicking, runs very now.
I would probably just say ok then do my own way (and also not share anymore videos apart from those normal lying down laughing videos - I am petty after I became a mum 😌). Cause from their POV they are just worried so I wouldn’t bother too much on what they said.