i have a random stupid question...

i keep wondering... the z fold is amazing but a small idea hit me and i need someone to tell me what are the downsides of using this idea...

the idea is why cant we just put two seperate glass screen protector on each side of the screen? leaving the middle exposed for when phone folds.. and as long as the middle part of the screen can fold freely then no issues will be caused right?

i admit i may not understand how these folding screens work or how sensitive they are to such ideas..