X-T4 noticeable "flecking" in low light - am I crazy?

Hey all! Got a used X-T4 today, and, as we all do, have spent the evening playing with the new features I'm getting coming from my X-T3. One of these is IBIS for still shots - I wanted to see how slow of a shutter speed I could now hand-hold on an unstabilized lens with sensor stabilization at my disposal! The answer lies somewhere between 1/8 and 1/4 which is absolutely remarkable, as someone who could rarely do 1/30 and even had issues sometimes with 1/60 without IBIS. This will be a low light game changer for me!

One thing I noticed, though, was noticeable "flecking" (I don't know how else to describe it) in the images even at a modest 3200 ISO with a 1/4 SS. It almost looked like stuck/hot pixels to me, but it could also be ISO noise as it got notably worse when I tried 6400 @ 1/8 and then 12800 @ 1/15. Here are the three pictures in question which are all underexposed to highlight the issue. It's hard to see until I pixel peep (which may be the answer to my own question - medicate my OCD instead.) https://imgur.com/a/Lu39SZy

When I do pixel peep however, even at 3200 ISO I can see notable white dots in parts of the image. https://imgur.com/a/r0WfGbQ

At 6400 ISO and 1/8, they become very clearly visible: https://imgur.com/a/E0LOGf6

...and then at 12800 they are pretty plainly apparent and numerous: https://imgur.com/a/QnvOxIv

See especially this portion of my wall in the shot: https://imgur.com/z3UUUTk

Is this Fuji's ISO algorithm, or would I really have so many potential troubled pixels all across the sensor on a camera that's been babied by it's previous owner (who I know personally, and treats his gear better than his loved ones). I was tempted to Pixel Map and then A/B but if it really is that I have this amount of pixels with problems, I'd want to do testing in more lighting conditions before changing anything. That would be a lot of software compensation I feel.

To have a comparison test, I grabbed my X-T2 and X-T3 and threw them on a tripod to get the same SS. X-T2 had notably more but similar in appearance of this "flecking," X-T3 I'd say handily beat the X-T4 at 3200 and 6400 (I could barely find any) but had similar and noticeable artifacts at 12800. For the X-T3 I even took one shot at 1/15 12800 and then ran pixel mapping and took the same exact shot. Nothing changed.

Honestly, the testing with other bodies eased my worry - but I still want to know, is this normal? Especially on a way newer sensor like the X-T4. I've seen and mapped stuck pixels on my X-T2 before and they typically appear bigger and even slightly longer than they are high for whatever reason- they look notably larger and more intensely "white" than these dots. These dots also, weirdly, seem to vary in size a bit and even appear "vertical" or "horizontal" on occasion as opposed to square. So I can I basically rest assured it's not a pixel problem on my new X-T4?

Thanks in advance for any help/affirmation (hah.)