Clearly many of the commenters here are somewhat younger than I am
Thos of us who are old enough can remember what things were like when telephones were a "government" thing - back when they were provided by the GPO which was back then still part of the government. Like the railways, the modern privatised system may well be far from perfect, but it's a darn sight better than what we used to have when services were provided by a government department, and didn't need to worry about promptness or customer service as your choice was to use them or go without.
With the GPO there was none of this "get a phone installed in a couple of weeks" - it could take months, or if you were unlucky, years to get a phone installed. I remember the phone in our last house was on a party line for many years because the GPO weren't prepared to put in cable to support needs - they just adjusted needs to suit what they had installed.
If you wanted more than one phone then you had to *rent* it from the GPO. If you wanted sockets then you had to rent those (and pay GPO to install them) as well - every item had a cost to it. None of this "buy your own and plug it in" malarky.
And dialling took ages as it was all pulse dial, with rotary dials !
Go back to that, no thanks. <mutter to himself>Youngsters these days, no idea …</mutter>
No I don't have a suggestion for what to replace the current system with. It's not perfect, but it's better than pretty well all the alternatives that have been suggested.
Having an equivalent of OpenReach owned jointly by all the providers wouldn't help. The larger ones would be able to game the system (adjust charges) so as to put smaller outfits and/or new entrants at a disadvantage. Plus, with BT as it's largest customer by far, it's fairly clear which tune they'd dance to.
Have them independent of all providers ? Same problem - they'll sing whatever tune the largest customer tells them to.
Have them independent but all charges set by regulator ? That's not much different to what we have now, and we can see how well that works - constant arguments about whether the charges are too high or too low. Plus it's still an incumbent monopoly so not that much reason to change anything.