This isn't so much an answer as some ideas for methodology, work in progress.
2nd Image from your answer, opened in Pshop & screen-shot pasted into here via Safari
Similar screenshot posted instead of pasted
The unfortunate discrepancy is if you look at the eyedropper colour, it says 226,61,36, yet both images in here are near-enough 255,0,0 - which means Pshop doesn't appear to know what to do with the Huion profile.
If I convert that to sRGB in Photoshop then screenshot it, it comes out OK. I'm going to have to guess that means the Mac doesn't know what to do with it when screenshotting from a "strange" profile.
If I generate a brand new image manually, sRGB right through…
PASTED to Safari…
POSTED to Safari
Then it reads as 255,0,0 in Photoshop, also on my Digital Colour Meter & when posted in here. Perfect workflow management.
I can still only draw the conclusion that there is something mis-calibrated in your workflow. It is not inherent in the Mac, nor in Photoshop.
[back in a sec to post via Chrome…]
PASTED into Chrome
POSTED into Chrome
Throw Chrome away & use a proper browser. That's rubbish.