You know full well that it does not matter how delegates are determined - the actual delegates are party insiders.
Most of the delegates are actually grassroots party activists - the people who man the phonebanks, stuff envelopes, work the GOTV efforts, etc. A certain percentage are the "insiders" - elected officials, party chairmen, etc. That is the nature of the system. If that is not the system Trump wanted to work within, he should have run as an independent, rather than as a Republican.