Our company has formally introduced hybrid working (having been almost entirely office-based before Covid). Basically you can work from home or the office most of the time, and then there are a few days a month that you have to come in to the office.
I think it works well. Some people were finding it lonely to work from home on their own and have started going to friends' houses to work from there, and that seems to be working for them. Productivity is as good as ever, and people are generally more relaxed because they have a couple of extra hours each day now that they don't commute. There are lots of little benefits - I find I can get a load of washing hung out in my tea break, so that's another 10 minutes saved (and I can hang it out in the morning knowing i can bring it in if it looks like rain, so I save on tumble drying!).
We've been able to recruit from a wider pool of talent because location isn't such an issue, which has made it a lot easier to get good, qualified people.
The main disadvantage I see is that it's harder to pass on knowledge, because you don't get those random conversations that you'd get in an office. However, we're encouraged to "chat" via Skype - it doesn't have to be all work-related - and that helps. I think as time goes on companies will find ways to fill that gap too.
We've been able to recruit a number of people who otherwise would struggle to work because of mental health issues, or who have physical disabilities which make a commute + office-based day quite difficult.
We have a couple of women on the team now who have DC with Autism; the DC find it difficult to cope with after-school care or a childminder, so these mums couldn't work because they had to do school runs and wouldn't have had time to get to the office (only really accessible by us or by car + fairly long walk) and work a half day in between; now they can fit it in between school runs because they're just going to school then home.