my personal distinction I use is about measurements. while you may model to a specific scale for use in 3d gfx (game by engine/animation/vfx) you cross over from "modeling" to "cad" as soon as you are creating geometry with specific real world measurements. (probably for manufacturing or engineering reasons bc thats when it matters most)
like I can model a table that is the right size and looks like it will not tip over for my game, but I am going to cad that table to run a stress sim and make the plans for building it for real.
though id still call the action of doing the building in the cad software "modeling"... so idk.. language is weird.
so software that lets you work accurately with measurements and real units == cad. (fusion360) software that just makes geometry == modeling. (blender)
but if you wanna go get real confused look at "plasticity" an app targeted at "modeling" but uses a cad engine and sells itself as "cad for artists" it has real scale
measurements and everything too.