If we look at the idea of a ”point particle”, it’s clearly something that is never observed elsewhere.
This is what leads to the whole idea of renormalization: that any force that goes to infinity as r->0.
For string theory, adding a second dimension to the particle adds density, which avoids the same amount of infinites. Similarly, loop gravity’s ”chunky” timespace also prevents infinites by essentially adding a minimum distance.
I feel both approaches are wrong. The conceptual model of the particle as a dot still lives on in some regard.
With M-theory, string theory moved more to something like the concept of a particle with density in multiple dimensions.
However, the extreme complexity and the many assumptions needed in string theory made it very unappealing to me.
I would like to see some theory that used the wave nature of particles resolve the infinities - including quantum gravity, then describe some mechanism how these waves could gain dual particle-like behaviour when leaving the Planck length world.