Hiding meeting controls without sign-in

I need to be able to hide meeting controls without signing-in -- the controls block the view of our presentations
and/or force the usable screen size to be too small.  Overall not being able to hide controls 
is a massive negative for zoom as a platform.  It should be easy and available all the time.

I use zoom a lot from many locations for meetings.  A typical use is to share a screen (e.g. for a presentation)
on a separate, public computer that manages a large screen or projector (e.g. in a conference room).   
I need to be able to hide meeting controls on that computer without a sign-in.  It does not
work at the moment -- there is no “hide meeting controls” option offered.

It is not easy or convenient to sign-in as my organization strongly discourages signing-in on public computers.
In addition, the organiztion has multi-factor login and it takes a while to sign-in.
It als forces me to bring the necessary tools for my MFA to every meeting which is onerous.
On public systems as I cannot stay logged in and I need to be sure I am logged out.  This creates
security risks and issues such as when I need to leave a meeting early or arrive late.

I know it is possible to sign-in and change the (annoying) default setting that is
“always show meeting controls”.  This is a bad default and it seems to be stuck on if you do not sign in.
You could help me a lot by getting rid of this default or providing some other way
to hide meeting controls without signing-in.