I WFH at my employers request. Productivity went up when we all worked at home during Covid so WFH has stayed in place.
We now use hot desks on the 1 day per week that we're in the office. It all works really well. My day in the office is my least productive day, I find it very noisy!
People who get annoyed about others working from home and claiming that 'they don't do the hours' are probably just thinking about how they would behave if they had the chance to WFH.
WFH offers great opportunities for those who physically can't get into an office and literally opens up a world of opportunities to everyone. Being able to WFH has given me opportunities in countries outside the UK. WFH also means that companies get the best person for the job not the person who lives closest to the job.
WFH has clearly worked so well for many businesses, that now a 4-day working week is being considered. I'm not sure I'd want to work longer days but just because it's not something I'd choose to do means that I'd want to stop others doing it.
I think it's great that alternatives to the working week are being looked at.