There is whole LARP scene of FIRE and influential bloggers from that scene are the only ones that are making money.
Nest egg I do believe had merit back when there actually were "high yield savings accounts" available. I basically see who is LARPing money management when I see they post about FIRE or HYSA, well "money market accounts" seem better and kind of like of HYSA, but the hell those are not really that easily available.
Government bonds are also rather interesting for keeping as "nest egg", corporate bonds are useless.
Article author seems to be from quite well off family lamenting he just didn't understood any of financial stuff and world moved on while he ate away whatever he had. Sad part is it can happen to any of us even if we are financially literate because market can be bad far longer than we can afford or like retirement, jobs all of this can shift while we are left with much less for day to day. Part that I don't understand is that, we should expect that outcome rather than be surprised by it. We should be surprised when all went well and there was no recession, layoffs during our lives.