Scopes and irons on rifles - depending upon what they're for.
Irons on handguns.
The only remaining red dot in my safes is mounted on an AR that's intended for short-range work, or snap shots on big game.
Scopes for precision.
Dots for speed.
Irons for various degrees of precision - and speed where the design favors such.
I like the simplicity of iron sights, but don't like certain designs that tend to be fragile.
As such, I designed a rear sight for my Marlin rifles, that I call the "Bulletproof Buckhorn". It's a solid piece of 4140 steel, milled to shape, and held in place by four 6-48 screws. Windage adjustment is coarse (loosen the sight, move it sideways, tighten back down). Elevation adjustment is done with a file. I pair it with fixed front sights held in place by screws (no dovetails for things to slide in).
Once set, nothing is going to change, short of the entire rifle getting folded in half.
Only half a dozen or so shooters have tested it, besides myself, but everyone that has used it loves it.
Fresh off the mill, before hand finishing (primarily 'de-horning' and chamfering):
Yes, that's a kaboomed receiver. I didn't do it. But I got the sloppy seconds for a good price, and use it as a holding fixture and a reference sample when prototyping parts or making something for a project.