I watched the first episode last night and the second one today.
The earlier episodes were great, but I think the series is well past its prime, for all of the reasons so many of you have articulated.
There were a lot of things which jarred, because they wouldn't have been said or done in the late '60s or early '70s. For example, one of the escaped convicts made a reference to a pina colada. I doubt very much a hardened criminal of that era would have been familiar with cocktails. Miss Higgins's grandson appeared to be wearing a Christmas jumper. The radio announcement about Reggie's disappearance referred to him as having Down's Syndrome, but I suspect they would have phrased it differently back then. However, in this era of cancel culture, I can understand why they didn't open up that particular can of worms.
As pps have noted, the Cork accent is very distinctive. There's no way that Nancy hails from anywhere near Cork.
Trixie and her husband were bankrupt in the last series, but now she has the money to fly home at the drop of a hat - and I can only imagine how expensive transatlantic flights would have been back then. Also, she was laden down with shopping bags when she arrived. She referred to the business as doing well, but they appear to have made a lot of money in a very short space of time. And who is looking after Jonty while she's away? Matthew? And Trixie didn't seem remotely upset or disappointed that she wouldn't be able to spend Christmas with her DH and stepson.
Cyril (the mechanic/engineer/Social Worker/pastor) continues to loiter around aimlessly. He doesn't appear to have any job at this point - he's just ready to step in whenever there's an issue. They're definitely setting him and Rosalind up as a couple. They just need to dispose of the mad woman in the attic Lucille.
Mrs. Turner is still the perfect Stepford Wife. She manages to combine motherhood and midwifery with ease, but still finds the time to rustle up award winning mince pies and conduct the children's choir.
I can overlook some of the above - poetic licence and all that. But too much of it and it makes for a very unrealistic series. It contrasts sharply with some of the very difficult and shocking storylines in the earlier episodes. I'm sure everyone remembers the storyline about the backstreet abortionist and the domestic abuse/paedophilia storyline featuring Anita Dobson (iirc, this was also a Christmas special).
Anyway, back to the storylines.
I think Dr. Turner someone should have died of flu, to make it more realistic.
I correctly diagnosed jaundice in the fairground couple's baby.
The family who were evicted have been described as Dickensian, but I suspect there are a fair few families in the same predicament today.
I have a soft spot for Fred and Violet and they can usually be relied on for a bit of humour, but they were very subdued in the Christmas special, owing to Reggie's disappearance.
The most interesting scene was probably the one in the kitchen featuring Sister Veronica and Geoffrey. She confessed to liking him and for a minute I wondered..... But I think the brandy loosened her tongue and she was just being honest and expressing affection for him. Is she having doubts about her vocation? I mean, nuns don't usually expect to have babies. And he in turn seemed to be hinting that babies wouldn't be on the cards for him.
The conversation between Sister Julienne and the official (is he a Council official?) also struck me as realistic. He was dripping with contempt for her and viewed the Order as standing in the way of progress.