inflation is good as long as there is something that keeps on sucking it(a thing that is deflationary), like for example bitcoin, if people start put their inflated money into a deflationary system like bitcoin, it would create an equilibrium , that will help the crisis
Wealth moving from an inflationary instrument to a deflationary one only serves to exacerbate both states. The only equilibrium implied by this simple description is in the hyper-inflationary annihilation of the former.
The inflationary instrument would have to have some functional advantage over the deflationary one to not suffer this death. This works for fiat money relative to gold because fiat money is much cheaper to move and store. This works today for fiat money relative to Bitcoin because Bitcoin is not widely accepted. If Bitcoin were universally accepted then I'm doubtful that fiat money's remaining functional advantages in paying taxes and settling debts would be enough to save it.
this mean that bitcoin can't reach mainstream without destroying fiat money i'm right(at least is what i'm understanding from the last part of your quote)? so we can't have both, side by side, without one not killing the other
I do expect that a healthy, truly accepted cryptocurrency would kill off a fiat rival in short order.
I will clarify though to say that by "Bitcoin universally accepted" I really mean "humanity truly accepts Bitcoin for what it is". Here I intend a much stronger statement than simply "going mainstream". Going mainstream to me is about most people people technically owning and using bitcoins but continuing to allow their financial activites to be tracked, regulated, and taxed. I was talking of a hypothetical scenario in which most people actually
use Bitcoin, allowing themselves the greater liberty and privacy the technology and supporting tools will allow; reclaiming lost freedoms of decades past.
To illustrate this distinction, please consider an extremely popular, MPAA/RIAA designed and approved, file-sharing service which automatically ensures that all copies made are fully paid for. Certainly, the MPAA/RIAA could co-exist quite happily with mainstream file-sharing in this world. However, the file sharing situation we actually have is much sharper and, were Bittorrent to become universally accepted by the people, I doubt the MPAA or RIAA would last very long at all.