I’ve worked in two high profile companies with very prominent apps on the Apple App Store.
The team we talked to at Apple never ever cared about our problems, but very often invited us to their office to discuss the latest feature they were going to announce at WWDC to strong arm us into supporting it. That was always the start and stop of their engagement with us. We had to burn technical support tickets to ever get any insight into why their buggy software wasn’t working.
I am glad that your experience is not the rule, as the OP reveals above. However, I worked for a company about 10 years ago with a fairly prominent app. An update that came out that absolutely destroyed the performance of it. At the precisely the same time, a competitor launched an app which did not have the performance difficulty. It turned out that the developer of the competing app had recently left Apple, and left an undocumented surprise in Apple's video drivers that broke it. It took disassembling the competitors binary to find the undocumented change and repair our application. The developer also taunted our CEO by email. Nice world we live in.
The team we talked to at Apple never ever cared about our problems, but very often invited us to their office to discuss the latest feature they were going to announce at WWDC to strong arm us into supporting it. That was always the start and stop of their engagement with us. We had to burn technical support tickets to ever get any insight into why their buggy software wasn’t working.
Apples dev relations are not serious people.