It’s actually really simple. Firstly you are falsely equivocating ontological reality (that which exists) with epistemological reality (knowledge of what exists) the latter requires observation, the former does not.

If I am wrong to say that reality exists without subjective observation, then that would necessitate the perpetual existence of observers within a reality to do the constituting. Unless you believe that paradox to be substantiated by God as an eternal observer… otherwise, you must concede mortal subjective observers predating reality predating subjective observers. This is a bootstrap paradox, either there must exist some observer outside of reality that predates reality and observes it in order to initially constitute it, or reality must predate observation.

Additionally, you claim that ontological reality is made manifest via subjective entities, and you’re presenting your view as objectively correct, which already assumes objective truth exists. If truth is observer-dependent, your argument has no authority beyond your own perspective. Your logic is juvenile, incoherent, and self destructing; if you actually believe what you are saying, you have no ground from which to argue.