I've acquired a lot of excellent quality belts & belt holsters over the years of my LE career, and then into retirement.
After enough time, when it came to both uniform, plainclothes and off-duty weapons, I pretty much considered "heavy" to have arrived at 39 ounces. (Based upon weights of my last service revolver and some steel-framed S&W 3rd gen guns.)
Pocket holster carry weight starts to get a bit too noticeable and occasionally bothersome,
to me, at over 15 oz (unloaded).
For belt holster carry nowadays, depending on my activities, manner of dress, etc ... annoying can start at as light as 20 oz.
Mostly, instead of simple weight, it's more the length of the slide/muzzle and/or grip height, as well as the thickness/girth of the grip frame.
The "best" holsters for my needs can certainly help mitigate this, and occasionally I may choose one of my different belts to accompany one or another of my different holsters (leather & plastic belt scabbards of various design/maker, as well as some different paddles). Just depends.
Having carried issued K & L-frame revolvers, as well as Medium & Large-framed personally-owned revolvers (Redhawks, N-frames, etc), as well as 5" 1911's & 4 1/4" Commanders, I've had some small experience with carrying largish revolvers & pistols. A 7 1/2" revolver presented some occasional difficulties in clothing selection.
Nowadays I much prefer smaller & lighter retirement weapons for CCW.