Interesting. I have never considered defensive shooting scenarios within my home to require precision shooting. I would think shots inside five to ten feet to be within the capabilities of most who handle firearms regularly. Mind you living in the areas I did over the years, the probability of such an event happening was right up there with winning the Loto regularly. That said, some of the houses I have owned over the years had straight line sight lines as much as 30 feet...still.
I do concede if your eyesight is severely compromised a slide mounted RDS may well be useful.
To add some real life insight into the discussion my neighbour, while living in another city, woke up to a home invader. His wife was stabbed and eventually bled out as he wrestled down the individual. No time there to turn in a RDS or even grab a gun to defend himself. Distances were inside of two feet. HIs arms bare witness to his struggles but he did prevail.
Circumstances vary and imaginations, propelled by marketing, can propose any number of scenarios, where one set up is better than another.
Innaavedaw of the examples illustrated it is worth noting only three examples, Glock, S&W and FN have co-witness capabilities so the options you suggest are not always there. Too, you also assume iron sights to be sub-optimal. Considering most self defense situations occur within five yards or less I would suggest any advantages of a Optic sight over irons are rather small when solving real life issues. There are advantages to Optics but perhaps not all that much as one might think for civilians. The exceptions being of course, shooting cardboard targets while playing IPSC, IDPA, 3 Gun or similar shooting sport.
Take Care
Bob
ps I do practice regularly with my Sig 320 Xfive with a Vortex 6 MOA mounted. Much easier to shoot fast and accurately, (inside 8"), once the dot is acquired at distances beyond 15 yards. Inside of 15 yards for me there is no practical benefit.
