I'm an academic - I do clinical research and I lecture at a uni. I've actually worked from home at least part of the week for about 15 years. It's quite standard in my field and none of my colleagues are ever in 5 days a week, even pre-COVID. What I do from home is a lot of project management/admin/data management stuff, data collection (which happens remotely because we can't secure funding for anyone to travel to collect research data anymore, so it's all online surveys and zoom interviews), and then teaching and teaching prep. Most teaching is f2f again, but not all. So I largely only go into the office when I teach, but that's only a few hours here and there. All the prep is done from home.
WFH is actually much more convenient for a couple reasons: (1) privacy - I have a home office with a door and I can assure privacy when I talk with people and many of the meetings I have are confidential, so I can't have them in an open plan or shared office. It's actually really hard to find a private office space if I'm 'in the office' as it's all shared or open plan, despite nearly all of us needing private spaces for confidential meetings! (2) I have reliable wifi - wifi in the office is hit and miss, some days it works, some days it doesn't! In my actual office, I don't even get wifi signal, I have to use my bloody hotspot on my phone to access the internet, which no one seems to care about and it uses up my data and can be expensive, so it's so much easier/cheaper to stay at home at use my home wifi which works perfectly well in my nice private home office.
Dh runs a small company that manufacturers particular technical bits for home/commercial kitchens. He largely works from home - he spends most days doing admin, organising shipping, dealing with customer issues, doing marketing, ordering supplies/raw materials, photographing products, website design, product development. He has a small manufacturing site in a warehouse unit with 4 employees and he is on site there once a week just to oversee things, collect orders, deal with any issues, tidy up stuff, sort out safety issues, etc.