Maybe a helpful visualization is one of the precursors to quantum field theory, Dirac’s sea.
The idea is that you can think of a particle as sitting on top of the surface of the “sea” while an anti particle is represented by a hole in the surface, large enough to fit one particle. When a particle encounters such a hole, it naturally drops down into it and settles there. This essentially “destroys” both the particle and the hole (the anti particle).
So essentially the opposite charge, spin, etc of a particle and anti particle are a consequence of their opposition in their fields, not the cause for the annihilation.
Maybe a helpful visualization is one of the precursors to quantum field theory, Dirac’s sea.
The idea is that you can think of a particle as sitting on top of the surface of the “sea” while an anti particle is represented by a hole in the surface, large enough to fit one particle. When a particle encounters such a hole, it naturally drops down into it and settles there. This essentially “destroys” both the particle and the hole (the anti particle).
So essentially the opposite charge, spin, etc of a particle and anti particle are a consequence of their opposition in their fields, not the cause for the annihilation.
(Not a scientist, grains of salt and all that).