Synchronous Replication: Where is data visible first?

Hello,

While discussing with the development team, an interesting question came
up: in a synchronous streaming replication scenario, with
synchronous_commit = remote_apply, will the change be first visible on
Standby (replica)? Primary will wait till the change is applied and
committed on standby, and hence logically this looks to be correct. But I
couldn't find this mentioned explicitly anywhere and hence seeking comments
from the community.

Assuming that the answer is yes, potentially the same can happen even with
synchronous_commit = remote_write | ON because on the way back to Primary,
if the network is slow, there is a chance that Standby may complete
applying the change and make it visible to the users.

Would sincerely appreciate if someone can share a documentation/blog link
that explains this, if there is one.

Many Thanks!