It would be a lot of work, e.g. just the plumbing for residential (kitchens and bathrooms in every unit) would be very different from plumbing for offices (a few central toilet rooms).

Electric, HVAC would be similar.

However, still could be possible in some buildings and ultimately be worth doing. For other properties it might be cheaper to raze and rebuild rather than try to fit residential space into a commercial-plan building.

Completely agree with other posts that the risk of loss should be squarely on the owners/investors. Property is an investment like anything else, and may lose value. And I'd guess commercial property is riskier than residential.

It's been done but very often "class A" office towers lack things which are needed for residential use, like windows that open, balconies, locations in the concrete walls and floor slabs for water and sewage pipes. Even basic things like if you take a floor of an office tower and turn it into 700 sq ft condos, how are you going to ventilate the bathrooms? Retrofit can be very costly.

https://www.google.com/search?channel=fs&client=ubuntu&q=qub...

I have seen some instances of older 1910s to mid 1930s era office towers in NYC retrofitted to (very high end, very expensive) condos.