Companies are still in the FA part of this whole thing. The FO part is coming. Personally, I love WFH but we're already seeing some negative impact at my company. The company still needs to lease building space, although they can scale back their footprint considerably. Conversely, they now have to open and operate 500 remote offices. At the moment, people are happy to use their home for that purpose but some employees are already starting to demand pro-rated compensation for things like rent, internet, electricity, etc. We've had a small handful of employees make Workman's Comp claims for injuries sustained in their home due to them sitting on the couch and using a coffee table for a desk, instead of a proper ergonomic workstation, which means the company might be obliged to supply literally everything that would normally be in an office or risk being liable.
We also have massively increased IT support costs since IT has little or no control over the quality and availability of internet at all these remote offices, and users just can't be bothered to come in for support. IT has to drive to their house when onsite service is required. In some cases, we've had to hire third-party remote hands when it's too far away.
At some point, it's no longer going to be cost effective to equip and maintain all these remote offices. If companies want to continue offering it, policies are going to have to be developed and laws are going to have to be crafted to protect both the company and the worker.