The UX/UI world has gradually come to be dominated by guidelines and aesthetics belonging to companies like Apple or Google. It’s absolutely normal and predictable that this would happen, considering most apps are designed to seamlessly fit into the user experience of technologies belonging to these big titans. The success of any product depends on its coordination with the existing services and that requires some level of standardisation, be it on hardware or software level. Design is directly impacted by the state of the market. Everyone (designers and developers alike) has access to Apple’s, Google’s or Microsoft's frameworks and guidelines. This way, even if one doesn't have much knowledge or experience in design, one should at least be within the safe zone when following those very specific structural and aesthetic advices. It probably won’t come out great, but it shouldn’t be a train wreck either.