Yesterday I had a thought about "people will agree with you only if they already agree with you" meaning that you yourself have a very small chance of changing their minds about something.
Tracing back to how they first formed their opinion, I think that the mechanism for convincing people is different for different people; some are more open to facts and logic, others more swayed by emotions and narratives. So it would seem that a one type of person would not be able to convince the other type with the strategy that works for them.
I think that for most people who have bought in to the covid narrative is because they are swayed by their emotions; a narrative is concocted/stitched together to sway the opinions of people who are vulnerable to that tactic. So, logically, in order to sway them the other way, a similar tactic needs to be employed. It doesn't have to be factual or logical in the factual sense, it just needs to be emotional and have an "emotional logic"; it just needs to make sense in the "rules of the world of the narrative" for it to be effective.
(documenting thought process behind it: I happened upon this thought while on a drive to a picnic and I was reminded of a anime I watched titled "Kyokou Suiri (In/Spectre)" where the protagonist fights a ghost of a girl who died who has been created out of a myth started by someone but evolved by all the superstitions tacked on by other people through an online forum. The protagonist wins the day by not by using logic or facts gleaned from police files about the case but by constructing an alternate narrative to steer the emotions of the online forum to dissapate the 'vengeful and murderous' narrative)
Probably not unlike how it is the tradition in America (and many parts of the world) how Santa Claus delivers presents or the tooth fairy exchanges teeth for cash; the narrative will hold sway in the young people's minds until it doesn't anymore; but I guess in the Santa Claus and tooth fairy example, their young minds start to mature and logic is creeping into how they think about things.
On another tack, as a parent of 2 kids, kids (well at least my kids) listen to me / believe what I say less (well, some things more than others) compared to influences outside the nuclear family. So I would guess some dynamic of that works the same; we'd have a harder time convincing out circle of family friends compared to an external source convincing them otherwise. That is probably it is a popular trope for families to have huge arguments and fights whenever they get together during holidays (e.g. Thanksgiving, Christmas, etc), well at least as depicted in movies or tv series.