The best argument against 100% work from home I've heard so far

HomeOffice was big during the Covid-19 pandemic. And it still is. Especially in industries where the place of performance can differ from the company's headquarters without having to fear a loss of productivity.
Ironically, these sectors were subject to numerous "return to office" (RTO) initiatives from companies that had previously praised themselves for enabling all their employees to work from home full-time. Admittedly, many of these RTO strategies were actually disguised job cuts. As, for example, not everyone who moved out of high-cost of living (HCOL) areas can or is willing to move back.
Naturally "thought-leaders" and other people voice opinions on why work-from-home is bad. Despite science showing the opposite pretty obvious. But recently I encountered the first argument I can understand and support completely.
It is about the training of apprentices.
The trainer said: "Normally, we would send the apprentices to various teams for six months. This allows them to learn about networks, databases and system administration for Linux and/or Windows. Some teams had to be visited as part of the training; for others, the apprentice could choose according to their own preference and desired area of specialisation. Nowadays, however, we are having problems finding teams where enough people are present each day to actually train our trainees. Training remotely is possible (§ 28 (2) BBiG (Vocational Training Act) in German law allows remote training "to a reasonable extent", not 100%), but it isn't nearly as effective. This is especially the case since many people in IT choose to isolate themselves and don't communicate proactively enough. Hence, opportunities are lost. For example, there are fewer opportunities to provide ad hoc support for complex maintenance work on failed mission-critical systems. If you are in the office, you can recognise these situations even without access rights to monitoring and can ask to sit nearby and observe or support. But remotely? Not always."
For me, this is the first genuinely compelling argument against working from home full-time.