Inherited OWNERS of a subgroup do not receive Request to join mail of project in subgroup

I have observed that in two groups. The structure is as follows:

MAIN-GROUP
- SUB-GROUP
  - Repo A
- Repo B

We have Creator 1 as OWNER of MAIN-GROUP and Owner 2 also as owner of MAIN-GROUP. If a user now request access to one of the repos the behavior is differently:

• Request Access to Repo B (in MAIN-GROUP) -> email sent to both Creator 1 and Owner 2
• Request Access to Repo B (in MAIN-GROUP/SUB-GROUP) -> email only sent to Creator 1 and not (inherited) Owner 2

However, I think (given that they are both OWNERS) both should receive the email in both cases. I have observed this behavior in a real repo and reproduced it in a test repo individually.