There have been many discussions concerning the use of the same or similar “Manuals of Arms” when it comes to training and practice. These discussions are, in my experience, always limited to semi-auto pistols.
Triggers, safeties (or lack of), decockers, hammers, strikers, even reloading (slide release, slingshot, over hand, belt, boot heel, etc)

What about the revolver users among us?
I would venture that MOST of us that carry revolvers, do so with something capable of Double Action or maybe even DAO.
Trigger systems should then be similar, only differing mostly in trigger pull or the ability to cock a hammer into SA mode.

But what about reloading?
I’m not really even talking about speedloaders v speed strips v loose rounds in a pocket.
SW, Ruger, & Colt (and I’m referring mainly to DA guns here) all use different methods for releasing their cylinders. Heck, the Colt even rotates the cylinder opposite the other two.
Doesnt that also need to be taken into account in training?
What if someone carries a GP100 but then has a small SW for backup? Or a Python for main carry, but an SP101 for backup?

Is this a thing? Should it be? Or am I over thinking (again)?

You are correct

With out practice, with any weapon you can loose time as you figure out how it works.

And it does take time to open the cylinder and reload

With a revolver the best way to get past that is to carry 2 of them.

And perform a New York reload when extra rounds are needed

And even that should be practiced, as its not natural to throw your gun on the ground because it's empty.....

Heck yeah it matters just as much! If I carried revolvers, I would only train and carry ones that open and have the cylinder swing out the same way.

Ditto for speedloaders, I'd only carry one type (of actual speedloader...speedstrips are OK to mix in since you can't even try to work it like a speedloader).