from what I can gather, it looks like the wordpress database in mariadb is set to that. See attached image
I think this is a migration issue. You've migrated post content from non-utf8mb4 to utfmb4 tables. So the content is already converted and damaged. Please confirm that the issue only exists in old posts. Can we reproduce the same problem now?
Yes, this was a brand new deployment for a PoC environment, so the problem existed since day 1 and has not changed since. The databases were not migrated, this PoC was recently setup from the ground up, the way it's presented in this thread.
Please try to reproduce the same problem here, just copy the original text (not the damaged text) and paste as reply. I think the problem is in the text you use. The text is not Unicode or it's copied from other softwares where the encoding is something else.
This isn’t a test but this!
I copied and pasted this from the same notepad that is not working in the environment I set up. Here you can see the tick mark works with a copy/paste.
(also I had an emergency come up and will be out of the office for the next 5 days, so i may not be able to respond until I return - apologies)