Handling errors in one spot doesn't work for all situations, though, right? Especially in an OO environment an object may need context for retrying a request, or some other kind of error decision making. So in practice some exceptions percolate through the object graph, while others are handled in-house, so to speak.
It works for most situations. If you need retry logic - exceptions is the wrong way to go. Errors returned by the standard library are most likely not errors you want to retry by default.
That depends, though, doesn't it? Just about anything network-related is subject to flakiness, disconnection, and timeouts. That means HTTP, database connections, sockets, etc.