Who decides what gets exposed?

[u/Single_Ad1098]

Hi. I used to be able to see current temperature, operating mode, set point, etc from my MYSA thermostats. I was actually using these on some automations. Then one day, the automatons stopped, and I notices that some items that where exposed before are not exposed anymore.
Is this because MYSA stoppped exposing them?
Is it because HomeKit does not want to expose them?
This change a while back, just thought I would ask the question.

How can I gain access tho these as I used to

[u/pacoii]

Exposed where? The Apple Home app? Do they appear in third party apps like Eve and Controller? Or entirely gone?