So what profession are we talking about...all the others I know off other than the military give some sort of relocation allowance or allow you to apply for a different posting. Medicine you get an email from an automated system one month into your current job telling you where you will be going to work in three months
Of the top of my head? Retail, hospitality, supply chain, logistics, several branches of engineering, many jobs in resources and a surprising number in pharma, the forces and of course areas such as academia which implicitly require mobility to progress.
There are many others, they simply spring to mind first as requiring significant upheaval or travel to progress in the career path. Sometimes simply at the low paid end with little prospects - certainly none of the status and kudos that goes with the title "doctor".
You are very quick to dismiss people who travel weekly or have monthly returns. That kind of travel has an exceptionally high correlation with divorce and family breakdown unless one spouse is both willing and affordable as trailing (and even then the divorce rate is high). One of my SiLs with young DC had 48hrs warning of her DH being sent to work in the far east for 6 months - only one return trip in all that time.
So tell me how many doctors do you know who spent 16 yrs moving house every 4 months? Because none of those in my extended family have had to move anything like that much, or for anything like as long. Their early years were tough as they are in any aspirational profession but they certainly haven't moved house /schools every 4 months