When you earn in bitcoin you will then opt to spend in bitcoin. Fiat then is reduced mostly to unit of account (i.e., prices still set in dollar (or other local fiat) terms, at least until the local currency is as volatile as bitcoin and then fiat disappears as the unit of account as well.

But what will be the catalyst to cause us to demand to be paid in bitcoin? Freelancers, sole proprietors, entrepreneurs, etc., have more leeway to begin the process of persuading customers to pay in bitcoin. Wage earners who receive a paycheck from their employer will have a harder time -- though there are now methods where the employer doesn't even need to do anything different (e.g,. BitWage gig worker mode, Deel, Hedge, Juno.Finance, Strike's Pay Me In Bitcoin, etc.)

Big question. Lots of aspects.

One surprising thing was talking to grand parents (or other old people) who still remember how it was when things were made to last. Like stuff was supposed to last a lifetime or longer.

Money wise I think its just about getting used to it. Denomination is crazy man 😂😂

it appears to be destroying itself.

Good question. Not sure if you can destroy it, but faith in it and comfort with it can be redirected to something else, such as BTC and the related mentality. Best way to do this is TV shows. I am totally serious about that. When an athlete gets paid in BTC and shows comfort with that in an interview, that shifts faith and comfort. If a sitcom character were to pay for a coffee with Lightening Network, that would shift the faith and comfort of the masses. Just like a sweater or pair of boots worn by someone on TV can instantly galvanize 100k people to buy that same fashion in the next 6 months, so can the demonstrated use of BTC shift fiat mentality to the use of Bitcoin. Homer Simpson buying a Duff with sats could do more than any well written evidence based article could. Just my opinion, that is most likely absolutely correct.

one at a time

By introducing a sound money mentality again. We had it in the world at one point, during the gold standard. People forget things after many decades, though. Time wounds all heals.

The fiat mentality was slowly gained, and must be slowly released as well.