Today it is more important to have different roles and experts in specific fields, but avoid making silos that others can’t understand. There has to be a common base for all engineers in the team, so that everyone can solve an incident in production for every part your application, it doesn’t matter if is on frontend or backend side. From my perspective as an SRE it is more relevant that everyone knows how you monitor your app, how to make the app secure, and where your logs are. Everyone has to know where are yours limits and always have a clear path to escalate and ask questions without shame.