Presenteeism for its own sake seems daft, especially when there are not enough desks.
As a general rule, people who take the mickey do that whether at home or in the office and vice versa.
Company wide mandates about set numbers of days in the office pay no heed to what happened prior to covid (sometimes it made sense for the same person to work remotely for a couple of weeks and be full time in office the next), especially when there aren't enough desks.
There are people at firms who want to be in the office more, but can't because others are using their mandated days to sit on earphones on meetings to people in other offices.
People who vary their work patterns depending upon the project and time zone they are working in. Teams at points in projects where it makes sense for them all to decamp to a certain office can't do this unless it's booked far in advance, taking no account of fluidity of projects.
People who previously would have just worked from home when there were engineering works traipse in - for what? Blanket policies don't work.
Some firms have benefitted by e.g. working from home when able while contagious, whilst others would rather other staff became sick but a tickbox of days in the office was met.
Many people work numerous additional hours to their contracts, are unofficially expected to log on in the evening, respond to emails OOH, write up reports etc. Commuting time (when unnecessary) on top isn't helpful.
I think for the firms that are mandating going back full-time where it doesn't necessarily make sense, this policy will be short-lived. As the next generation move into more senior positions and able to influence company policy, I think more flexible working practices will return. Also, as more and more people develop disabilities (long covid etc) it seems daft to increase inflexible working practices.