The fact that it is difficult to measure whether or not WFH had an impact on productivity or not is a HUGE mark in its favor. This should have just fallen apart, no consultant or advisor would have every recommended trying a mass remote working initiative this way. Instead it seems to have mostly worked.
I say mostly, because now we are at the point where it takes concious thought to build processes and culture to sustain a remote work culture. Developing young talent is difficult regardless of the circumstances, but in the in person office we have well developed norms, culture, programs, and processes to support them. Have you and your organization spent significant time thinking adapting and developing those cultural factors? I'm a remote work advocate because I've seen it work not just for me but for those around me, including junior talent, but you have to think about it, experiment, and work at it.
Beyond the workplace, a lot of people have complained about the sudden transition to WFH do to them being not set up for it. I've heard this expressed as because they have limited space / lots of roommates or just being uncomfortable with the lack of home/work seperation. The root cause of these is (mostly) the unique circumstances of this experiment. If WFH was a strong social norm, people would have chosen different living accommodations and would have "seperate spaces" without needing a corporate office.
While not every job ultimately can or should become primarily remote/WFH, I think the benefits for most information workers and their companies will win out. But right now we are going to see the long and hard process of rebuilding culture and norms in a new work environment.