Answering the direct question in a simplistic way: because this is the preferred style of collaboration for these employers you are talking about. Let me elabor

Answering the direct question in a simplistic way: because this is the preferred style of collaboration for these employers you are talking about. Let me elaborate. It is not good or bad, effective or ineffective, nor it is the case for all employers. Here is my take: the preferred style of work (office, remote, hybrid, flexible) needs to be shared between the team members. Not unlike people's values. If the vast majority of people on the team share it - you are golden. If everyone has their own - you have got yourself a problem. By all means, please, ask it on the interview! (Goes both ways, for the employees and for the employers.) Now, I understand that right now there are probably more pro-office employers than people willing to accept it. Whether it is true or not (do we have some reliable statistics on this? are we a vocal minority instead?), I think only time will create an equilibrium (new generation of middle managers, etc.)