ERF was new, very niche and very expensive when my teenager was a baby. I just didn't have a spare £400 to spend on an online, unseen product that couldn't be viewed in places like Mothercare, Toys R Us or Halfords that may or may not have fitted in my car.
The tone of the groups has not changed since the early 2010s.
It's the lack of nuance that is so frustrating.
The best that money can buy is not an even playing field.
The seat only has its maximum advantages when it's safely installed.
If a seat is going to be humped in and out of various cars, it risks unseen damage. For grandparents cars, it's often better to have a safely installed, well-fitting seat that the grandparents are confident using than a premium product compromised by poor technique.
The seat has to fit in the car. The car needs suitable fixing points. Older, smaller cars have fewer options avaliable.
The child has to be content. A screaming, child significantly increases the risk of an accident from driver distraction. A vomiting child is at a substantial choke risk. I knew a baby turned FF the moment they hit the absolute minimum because they would scream and vomit until they stopped breathing. That was not safer. Parent ended up pulling up randomly all over the place to check baby's welfare when all went silent. That was not safer. Safe driving with a quiet, breathing, FF baby was the better option in that situation! It is quite an extreme case, but I ended up turning DS1 sooner than DS2 because of the hazardous distracting nature of him screaming regardless of mirrors and toys. He was well within the legal range of that point in time, but not today. DS2 was happy until I could no longer fit him in the seat at all.
Fortunately the vast majority of families will not be in situations where the advantages of ERF are put to the test, and those advantages have diminishing returns as the child gets older. The risks of needing the additional benefits of ERF are about speed and driving style. In cases of grandparents and car seats, for occasional use, and local, low speed driving, the risk over the usage of a car seat is already incredibly low.
The sense of statistical nuance in these debates is dire.
In the wider world ERF has increased into toddlerhood with relatively recent changes in legislation, but it's still not standard practice in school age children.
The bigger issue in child/ car safety is the continued use of any age appropriate seat/ booster until it is legally no longer required. I have challenged grandparents ignoring the seat in the rear of the car and driving off from the school run with a toddler on a lap in the front seat 🤦♀️. I've also flatly refused to have under-height children of 7-11 yo in my car without a legal seat regardless of what they do at home. I'm the driver and I'm held legally responsible.
The typical dogmatic attitude of ERF discussions inhibits sensible discussion about less than perfect scenarios and prevents people accessing second-best solutions. That makes it more likely that they'll turn to less ideal options. Shame is a poor tool for education.
There's a lot of survivors' bias out there because there are millions of survivors of previous legislation and even pre-seatbelts. Despite the poorer outcomes in the event of a collision, a typical car journey was still a fairly safe thing to do over the course of life. Progress in car safety is of course a good thing, but it still needs some perspective about risk level (and yes, of course I'm glad that my children never repeated a slide into the foowell during abrupt braking like I remember)
Similar purity spiral echo chambers used to arise in BLW and babywearing groups (probably still do!)
Never be too zealous about parenting standards... the world will keep changing and your children/ grandchildren will grow up to be aghast about how cavalier you were against the new standards 😉