Outlook changing styles/colors of incoming email?

HI friends - I recently got an email from a research org named ORCid and I noted when I received the email that it was hard to read - the text was a lightt grey on white, or light grey on dark grey in dark mode:

I emailed ORCid back and explained that this was going to fail any WCAG/Accessibility checks, and could they take a look. I spoke back and forth with their internal developer who insisted that it didnt look like that on being sent - he sent me examples from his own inbox as proof:

And these look perfectly fine.

Weirdly - when I forwarded this email to a colleague, they showed me on their screen it appeared as intended with the tetxt darker and more legible.

They forwarded it back to me - and surely enough, it looks correct. This using the Outlook desktop app in both old and new mode - and dark or light profile - and also in the web outlook as well.

Im really confused as to how/why when I receive it the first time it looks so unreadable?

Any advice would be awesome.