Polymer handguns have been around since the mid-80's (G-17) and haven't changed dramatically much since then.
MRDS has only been completely refined for handguns in the last 5 years. You can't equate the use of a frame mounted tube sight to the impact a slide mounted MRDS takes...Thats not even close in the amount of force exerted on the sight and the mounting screws.
I started shooting red dot sights on competition handguns in the 80's. It was very common to take the scopes apart and epoxy all the connections on an annual basis. And everyone, I mean everyone had a back up gun.
MRDS on handguns is not a "little bit more maintenance"..its exponentially more maintenance.
It requires committed, periodic optic/mount checking, screw checking, and regular battery changes.
Metal fixed sights have zero maintenance.
I am an advocate of MRDS..heck I shoot better with them!
Do I need them on my gun to win in a fight? Confidently, I can say no. Unless I have to make head shots at 50 yards I think I am OK.
Slide-ride dots have been around (with or without milling) since 2010 or so. I had a Gen 1 RMR on an FN45 back in 2011–it was a demo gun for cans. Had probably 6K rounds through it by late 2012, and there were zero issues. Optics have only gotten more optimized since then.
I think you might be understating the issues with iron sights and overstating the issues with
properly installed modern optics.
Metal iron sights are not maintenance-free. They are just as prone to getting occluded with lint, debris, mud, dirt, and body hair as anything else. They need to be visually inspected after impacts and shooting sessions to confirm they haven’t moved or come loose. My old duty gun rear sight drifted almost completely out of the dovetail when I fell on it during a fight (Glock 21). Oversized Glock front sights (suppressor and/or tritium) bend and break at the tiny mounting screw if they are not installed properly and still need to be checked somewhat regularly, at least after exposure to high temperatures, vibration, or impact. Fiber optics break, tritium inserts come loose if exposed to certain solvents, heck, plain serrated sights can pick up dings and rust that ruin the sight picture.
Like anything, even fixed irons require PMCS and occasional repairs/replacement.
One the other hand, most “problems” with modern optics come from their proliferation with low-info consumers. If you spend the coin on a quality sight, buy quality batteries, use quality mounts/hardware, and properly clean and torque everything during mounting, the only way for something to go wrong is a true manufacturing defect (e.g. early circuit boards in Leupold DPPs).
Most consumers don’t know how to take these steps—they think blue loctite on dirty screws, twisted “tight,” is mounting an optic and/or a plate. They trust the factory assembly line install, which is almost never done properly (ahem, SIG). Most consumers don’t witness mark. They don’t use compressed air to clean the lenses every couple days. Most can’t even shoot well enough to zero the darn things.
Those people have access to the internet and take classes and visit ranges, and voila, now optics are “high maintenance” and more failure-prone than irons. They’re just not, and haven’t been for years. Buy quality, install correctly, blow off debris, check them after impacts, use witness marks—all the same steps as maintaining irons.
The only differences are battery changes and
depending on the model brightness management.