My employer has already been putting measures in place to what seems to be potential loopholes. Hybrid working was bundled as part of "flexible working", they have separated it out into a different terminology. The term Flexible Working is now purely for those who want to change their hours like removing a day once a week and getting paid less, or moving hours from one day into the other 4.
A large number of companies are pushing to get people to RTO and I get the feeling these workers rights won't counteract that.