To repeat, No single method works for everybody. We need all the methods because everyone is different.
My personal experience of Allen Carr is as follows:
Read the book, managed to quit for 2 days then relapsed. Went to the group (still led by Carr himself when he was alive) - relapsed before bedtime the same day. Took them up on their guarantee - you can go again if it doesn't work the first time - managed about a day and a half and relapsed again. There were people in that relapsers' group who were back there for the fourth or fifth time. I cut my losses at this point because although I could have gone back a third time (fourth, fifth ...) for free, the travel costs were not insignificant.
So Allen Carr did not work for me and I gave it a bloody good go. Nevertheless I know it works for lots and lots of people so I don't slag it off.
My personal experience of vaping is as follows:
I had to stop smoking for health reasons but didn't want to. I bought a vape (not even a very good one) and thought I'd 'practice' with it for a few weeks before setting a quit date. In fact I quit smoking completely the same day because it was so incredibly easy. 6 years on and I am still astonished that I am no longer a smoker. My health has improved dramatically, I didn't put on weight (I have since but that's another story), I didn't climb the walls with cravings. I accept that I am still somewhat addicted to nicotine, although nothing like when I was smoking. I have read extensively on the health risks of nicotine (very similar to caffeine) and of vaping more generally (estimated 5% of the risks from smoking, based on unknown long term risks from some flavourings). I'm happy with that because vaping gives me peace of mind - I'm relapse proof.
Nevertheless I know that vaping doesn't work for everybody so I don't plug it as the one true method.
All I would ask is that people don't spread misinformation about vaping. It's easily done because the press love a vape scare story but it makes the public health people tear their hair out. It puts people off switching, including the most heavily addicted smokers who have tried everything else already.
Long term smokers have a 50% chance of premature death, losing on average a decade of life. It doesn't matter how you quit, it just matters that you quit.
This video is by NCSCT who are the people responsible for training stop smoking services: