If you can’t work it out when several people have explained it to you already when in fact it doesn’t even need explaining to see the issue and why people have a good reason to be annoyed by this then as I said you’re just wasting everyone’s time including yours.
Your solutions to an issue that never existed on said product at launch and for a whole year are to either pay for a family subscription which wasn’t needed and pay 50% more AND have everyone elses Apple purchases tied to my card, which is absolutely never going to happen, or pay twice the price, £200 each year just to put that ability back which was there when a lot of people bought the product and Apple said nothing, if you can’t see an issue with that then you have a bigger problem than this and maybe more money. (By the way, I HAVE bigger problems than this just in case you want to go down that road).
For some people it’s very easy to not see a problem if they don’t have it, me, even if I wasn’t one of the people who bought this device in good faith largely on the ability of the device AS IT WAS SOLD, I would have still been understanding and sympathetic to those who did, but some like you seem incapable of such a thing so go deal the problems you DO have instead of being unhelpful and insulting here, that would be a win win.